[Sirea]

I don't think any Japanese music would suit a professional level recital at all...

The Japanese pronunciation and accent makes it so you wind up singing entirely out of the nose and your whole tone changes in a way most Westerners find annoying or strange.

If you choose to not use that Japanese style, it sounds like you're just an American awkwardly singing in Japanese with no knowledge of the language... sort of loses authenticity and the "culture" of the song.

Sort of a lose/lose situation. I've always wanted to sing Ayu songs for performances but I know it's not realistic, since on a professional level not only is pop music typically frowned upon but Japanese is not a language formally taught/used by voice students and their instructors.