Roblox doesn’t like images like this because of their ties with fetish material, as far as I know. I don’t feel like elaborating anymore than that.
The fact that another version on this same image with a different color is surprising to me though.
I’m very surprised you’ve been banned over an image like such (which I personally don’t see anything “inappropriate” about this image), like I deeply struggle to see what Roblox is trying to “protect” by terminating this image and your account, even if the reason was fetish material - I don’t see a termination being logical, anyone can have a “fetish” for just about anything (take hair for example, as weird as it may sound - there are sexual hair fetishes lol) so what’s are solution? Banning hair? Lol.