[Topic renamed as discussion broadened from original topic]
[Original title: Chopin’s name in MB]
The guidelines were written for performing artists, but there are no specific guidelines for composer, so I would assume that the same guidelines are applicable.
While Chopin legal name was indeed Fryderyk Chopin, he has spent most of his life in France, and has therefore been performing and known as a composer as “Frédéric Chopin”.
Even while he was in Warsaw, his first work (the Rondo in C minor Op. 1) published in Warsaw has a French title, and used the French version of Chopin’s name.
Full original title of Rondo in C minor Op. 1
The same occurs for other work published in Vienna before his move to Paris.
So unless we take for composers a different approach from other artists, I believe that Chopin’s name in MB should be “Frédéric Chopin”.