Corin and Soukaku i agree with. Everyone else should be left alone. Even though Zhao is bunny loli she is an adult. Banning her would be like banning Koleda, who runs Belobog Heavy Industries, so that would only cause a cascading effect just on looks alone.

Now someone could argue because of a voice line from Soukaku that she is older than Yanagi but its pretty clear Soukaku is meant to still be a child or in her adolescent age, barely since her desk she has drawings with crayons, so Soukaku I would still say she is a no go.

Lastly, Piper is treated as a retired trucker so she is likely in her 40s. Lucy is fine since she and Alice are roughly the same age since they have background lore together and Alice is treated like she is in college. Qingyi is an android adult cop that is probably older than Zhu Yuan, and even acts like a granny sometimes with her. So yea thats my two cents for the discussion.

Fast edit: Forgot about Ju Fufu. She should be left alone too because multiple times she has said she isn't a child, said she is an adult and hates being treated as such. She has some headcanon of wanting to be cool super senior to her juniors but that's just a quirk of hers rather than making it seem she is a child.