It's kind of interesting how this premise has been trying to work for years now, with mixed success.
Girl with multiple personalities, girl whose personalities all split into their own bodies, girl who has multiple personalities but they don't remember each other, etc., etc. Funny enough, this mangaka already tried a "split personality" premise with a oneshot he did years ago. You can find it here on MangaDex under his other alias: Huro.
https://mangadex.org/author/56a421b7-2130-4755-9244-16807c3126bf/huro
Nah, I doubt it, after all, his artstyle have always been like this, even back in the 2010s, and his characters have always been the very forward like.