How to name an artist that has the same name as their own character?

So there's a Vtuber, Kasai Itsuki, who has a character tag already. But she's also an artist (who draws that character), and there is no currently existing artist tag linked to her Twitter or Pixiv. I'm trying to create an artist tag, but the system won't let me because "kasai_itsuki" is already taken - but there's no other handle she goes by that I can find, so I don't know what the alternative is supposed to be. The wiki explicitly says not to use "_(artist)".

I believe this is one of the time you're allowed to use _(artist) qualifier for VTubers that also draw (usually as their persona). Shirakami Fubuki is one such example.

You can qualify the tag with _(artist) in this case.
Sniped~