Andreas is a beautiful name, with the patina of an Old Master painting, one that could make a dashing namesake for an Uncle Andrew. 
 In Europe, Andreas is currently in the Top 20 in Norway and is also popular in Denmark, Sweden, Germany, and Austria.
Some other international variations of Andrew you might want to consider — Andre, Andrei, Andres, Andrea, and Anders.
 Notable namesakes include photographer Andreas Feininger. One not-so-pleasant association: the San Andreas fault line in California.

Andreas

Works better as a full name than Arnie does as a nickname. 

Arne

In Spanish cultures, and spelled either Bastian or Bastien, this is a fairly common nickname name. The German fantasy children's book The Neverending Story features a young boy character called Bastian Balthlazar Bux, and it has also been seen in several screen versions. 
 Bastian has been enjoying recent popularity in Latin America: it reached Number 11 in Chile--as well as in Germany and Scandinavia, and is just beginning to be appreciated here. Jeremy Sisto used it for his son.
 Alternate spelling Bastien is also a fashionable Euro form with a possible future in America. There is a one-act comic opera by Mozart titled Bastien und Bastienne.

Bastian

This Nordic-sounding name is ripe for wider usage, especially as a fresh alternative to Christian or similar-sounding Carl.

Carsten

This surname related to Clement is strongly associated with Major League pitcher Roger Clemens, winner of more Cy Young awards than any other pitcher in baseball history, and has a softer sound than Clement. Some variations are Clemen, Clementio, Clemention, and Clemons.

Clemens

Denis

Dieter is a classic German name that got lots of satiric exposure via Mike Myers on "Saturday Night Live" a few years back. If mispronounced, it could conceivably be read as someone on a diet. 

Dieter

A perennial classic in the Netherlands, short-and-sweet Dirk is starting to feel like a fresher alternative to cousin Derek.

Dirk

Fabian is the ancient name of a saint and pope that also has Shakespearean cred as Olivia's servant in Twelfth Night and more recently made an appearance in Harry Potter. In the U.S. Fabian became best known via the 1960s teen idol/singer who went solely by his first name.
 The name was brought to England by the French around the sixteenth century. Except for a few scattered earlier appearances, Fabian has been solidly on the U.S. pop list since 1959. It is a particularly <a href="https://nameberry.com/popular-names">popular name</a> in the Latino community and even more well used in several other countries, including Austria, Chile, and Poland. Fabiano is an attractive <a href="https://nameberry.com/baby-names/506/italian-names-for-boys">Italian name for boys</a>.

Fabian

If Flora and Florence have returned full force, Florian, with its trendy Latinate ending, could also have a chance. Popular in Germany, Austria, Switzerland, Poland, and France, St Florian was the venerated patron saint of those in danger from water and the patron saint of firefighters. 
 The second century Roman martyr St. Florian appears in Tennyson's poem "The Princess," and also in Gilbert & Sullivan's comic opera "Princess Ida." Sir Florian Eustace is an off-stage character in Trollope's novel The Eustace Diamonds, Florian Fortescue runs an ice cream shop in Harry Potter, and Florian is the real first name of singer Dido. 
 
Stylish Florian could be a great way to honor a Florence (or a Lily, Violet, or Rose) and it fits in with other gentler names like Gabriel, Elias, and August, that are in style for boys.

Florian

Franz is the German equivalent to Francis, and you'll be hard-pressed to find a Franz outside of countries with Germanic origins. In America the name is often associated with celebrated author Franz Kafka, who was born in Prague.

Franz

Both a saint's name and a presidential one via Gerald Ford—who was born Leslie—Gerald is a quintessential 1930s-40s name, when it ranked as high as Number 19. Hence all those nice middle-aged and senior Jerrys we've known and loved. Gerald has always been popular in Ireland, accounting for the prevalence of Fitzgeralds there. Though not considered stylish, Gerald remains on the popularity charts. Cousin Gerard has a similar profile, Geraldo is the well-used Spanish version, and Geraldine is the most promising of the family, in line to follow the path of Josephine to imminent revival.                                                                                                                                                                                                                                                                             

Gerald

Johannes never caught on in the US, but popular European short form Hannes may be more accessible.

Hannes

Harald

Heiko

Traditional <a href="https://nameberry.com/baby-names/160/german-names">German names</a> of this ilk have had a difficult time emigrating into the American name pool, mostly because anti-German sentiment during the two world wars of the 20th century drove <a href="https://nameberry.com/baby-names/160/german-names">German names</a> out of fashion. One of Heinrich's nicknames, Harro, might do better.

Heinrich

Heinz has become a cartoonish German name, prone to ketchup teasing. 

Heinz

Photographer Newton...or that hard thing you wear on your head. 

Helmut

Names ending in bert have long been in limbo, but with the return of Albert, maybe there's hope for Herbert. who could share the Bertie nickname. Herbert is a name that's been used by English speakers since medieval times, and was in the Top 25 in the US in the late 1920s, around the time of the presidency of Herbert Hoover, but there's been no sight of Herbert in the 21st century. Some Herberts, including novelists H. G. Wells and H. E. Bates, have preferred to go by their initials.

Herbert

A standard form of John in Dutch, Swedish, Norwegian, Danish, Czech, Polish, Slovene, German, and Catalan. Properly pronounced yahn (in most of these languages), most Americans will still equate it with the Brady Bunchesque girls' name Jan.

Short but substantial Nordic name that travels well -- although it runs the risk of being confused with all the feminine Jen names. 

Jens

Joachim is an undiscovered biblical name with potential, although most modern parents would probably prefer the more lively Spanish version, Joaquin. Like many Old Testament names, it was primarily in use in the seventeenth century, and then became rare. In the Bible Joachim is a king of Judah; according to the Gospel of James, Saint Joachim was the husband of Saint Anne and the father of the Virgin Mary.
 br/>Currently well-used in France, the name Joachim is known in countries and languages around the world and pronounced somewhat differently in each. While American might be most familiar with the Spanish version of the name, Joaquin via actor Joaquin Phoenix, that pronunciation wah-keen is not similar to any of the pronunciations of Joachim, which all have three syllables often with the emphasis on the second.

Joachim

Still very Old European, conjuring up the image of a classical composer. But surprisingly, it's now been in the Top 600 in the U.S. since the turn of the 21st century, largely thanks to Heidi Klum and Seal's young son.

Johan

An Old World name that might have a chance to rise again with other ancient and worldly forms. Be sure to say yo-HAHN-es.

Johannes

Jurgen

Kai is an internationally flexible name with many possible origins and meanings, growing in popularity in the US and a diverse range of European countries.
 
In the US, the name Kai is most commonly referred to as being of Hawaiian derivation, meaning "sea." In Europe, Kai is largely considered to have Frisian origin as a diminutive of the name Kaimbe, meaning "warrior", or as a short form of Gerard "brave spear". 
 
Kai is also found as an independent name in African, Chinese, Turkish and Native American cultures. Kai is a strong, evocative multi-cultural name that packs a lot of power in its single syllable. 
 
Famous as the name of the boy enchanted by the fairy-tale Snow Queen, Kai was chosen for her son by actress Jennifer Connelly and as a middle name for son Samuel by Naomi Watts and Liev Schreiber. 
 
Kai is popular with Berries as both a first and middle name choice. Perhaps because of its international familiarity, Kai is popular in video games. Its most prominent namesake is Danish-born jazz trombonist Kai Winding.
 
Kai ranks in the US Top 1000 for girls, but is used more than 90 percent of the time for boys. Donald Trump, Jr. has a daughter named Kai Madison and Gigi Hadid and Zayn Malik named their daughter Khai in 2020.

German, Scandinavian and Polish spelling of Konrad, borne by several German and Polish rulers throughout history, as well as the German chancellor Konrad Adenauer.

Konrad

Marcel, despite distinguished namesakes including Proust and Duchamp, suffers from a terminal headwaiter image in this country. But along with its sister name Marcella and French variation (and Jolie-Pitt pick) Marcheline, Marcel may be on the brink of a style renaissance.
 French Oscar winner Marion Cotillard named her son Marcel in 2011.
 Fans of the sitcom Friends will remember Marcel as the name of Ross's pet monkey.

Marcel

The K may be trendy, but this spelling variation is much less popular than Marcus.

Markus

The unusual-to-the-English-ear Moritz is a Top 25 name in Austria and a form of Maurice or Morris, which are modern variations of the ancient Roman Maurus. There were several early saints named Maurus and a famous 3rd century Saint Maurice, who was a Roman infantryman who was martyred when he refused to worship Roman gods. The Moritz form also references the posh Swiss ski resort St. Moritz and Justine Moritz is a character from Mary Shelley's novel, Frankenstein.

Moritz

Mittias

Oliver is an international star, ranking near the top of the charts in the US and throughout the English-speaking world, along with a host of European and Latin American countries, from Norway to Chile, Slovenia to Switzerland.
 
Long a popular choice in England, Australia and New Zealand, Oliver entered the list of Top 100 <a href="https://nameberry.com/boys-names">baby boy names</a> in the U.S. for the first time in 2009, but has already jumped to the top of the charts. Why? Because Oliver is energetic and good-natured, stylish but classic, with a meaning symbolizing peace and fruitfulness. 
 
Oliver derives from Olivier, the Norman French variation of the Ancient Germanic name Alfihar ("elf army") or the Old Norse Áleifr ("ancestor's relic"), from which comes Olaf. Olivier emerged as the dominant spelling for its associations with the Latin word oliva, meaning "olive tree."

Oliver was used as a given name in medieval England after the spread of the French epic poem ‘La Chanson de Roland,’ which features a character named Olivier. It lost favor after the seventeenth century rule of Oliver Cromwell, then was revived in the nineteenth century. 

Oliver's biggest boost in this country came from the hit book and movie Love Story, which also catapulted the name Jennifer to stardom. Notable namesakes range from Oliver Wendell Holmes to Oliver Hardy to Oliver Stone. In fiction, there is Oliver Twist, and Oliver is also a Harry Potter name.
 Oliver works particularly well with single-syllable surnames, as in Oliver Stone, North and Puck (son of Wolfgang). Other celebrities who have chosen Oliver include Bridget Fonda, Fred Savage, Stephen Stills, and Taylor Hawkes. 
 International forms include the French Olivier, the Spanish Olivero, and the Italian Oliviero.
 Parents considering Oliver for their sons might consider that with Olivia at the top of the charts for girls, there will be an awful lot of children with names starting with Oliv-.

Oliver

So simple, yet so unique: a prime candidate for export. Pronunciation is like the English pair or pear.

A variant transcription of Russian Pyotr, and also the Polish and Belarusian form of Peter, classic and still very popular there. 

Piotr

Ralf

Rudi

Especially for parents of Scandinavian descent, Sven is an accessible and attractive name with an appealing mix of strength and swagger. It comes from the ancient Swedish tribe, the Sviars, who gave their name to Svealand, which later morphed into Sweden.
 Sven is now most popular not in its native Sweden but in The Netherlands, where it is currently in the Top 20. But for many parents in English-speaking countries, Sven is one of the most quintessentially <a href="https://nameberry.com//baby-names/190/swedish-names">Swedish names</a>.
 An internationally noted bearer is Swedish cinematographer Sven Nykvist, known for his work on Ingmar Bergman films. Svens have appeared as characters in Titanic, Pixar's Cars (voiced by Arnold Schwarzenegger), as a Nintendo Pokemon and a manga character, and Marlon Brando portrayed an unlikely Sven in one of his late movies, Free Money.

Sven

Thorsten

The modern name Till is in the German Top 100.  Used in contemporary terms on its own, it's traditionally a short form of names beginning with Diet such as Deitrich, which is itself a form of Theodoric.  Because of its English word equivalent, it's a bit slight to ever make it as a standalone name in the English-speaking world.

Till

Tobias is one of a number of s-ending <a href="https://nameberry.com/boys-names">boys' names</a> that are riding a wave of popularity. With its Old Testament-Dickensian feel, it's a name with a distinguished pedigree. 
Tobias is the Greek form of the Hebrew Tobiah, which was derived from the name Toviyah. Toviyah was created from the elements tov, meaning "good" and yah, representing the Hebrew God. Tobias is the name of several biblical figures but is primarily associated with the story of Tobias and the Angel.
 A contemporary bearer is Tobias Wolff, author of A Boy's Life. Tobias Smollett was a major eighteenth century Scottish novelist. Tobias Snape, meanwhile, is a Harry Potter character.
 
The short form Toby has a life of its own, used independently at least as far back as Shakespeare's time, with Sir Toby Belch in Twelfth Night. Toby also was the name of a character on The West Wing. Actor Tobey Maguire was born Tobias and named his son Otis Tobias.
 
There is also the rarely used but still viable daddy of them all --Tobiah, the name of a rebel Hebrew king

Tobias

Chef Wolfgang Puck has helped soften this thunderous Germanic name; music-lovers will appreciate its association with Mozart, though the composer's middle name Amadeus is more appealing. 

Wolfgang

binia's list "German Boy Names" of 41 great name ideas: Andreas - Wolfgang!