Board Thread:Off-Topic Discussion/@comment-6433273-20151126190829/@comment-5051846-20151213115454

Basically: we know that Avanna was changed to look more anime, but we don't know Yamaha is requesting that for everyone.

Aki speculates on why:

(It is in my personal opinion that Yamaha made this quest due to the shocking response from the fandom with Voctro Lab’s Clara and Bruno original artwork. [...] This is, of course, just a personal opinion.)

(She says it is just her personal theory)