Which one is better?

Both are compatible 👍🏻✨ Both have their good points and areas for improvement, after all~

If you're satisfied with pretty, shojo manga-like writing, then Chacha is perfectly fine. Zeta right now is lost in its own maze, perhaps too much so. Honestly, you might as well try out various AI chats, not just those two options...

Chacha, I took a look once, but there aren't many characters, are there? For Zeta, something pops up when you search. I prefer Chacha because there's less advertising. Since my favorite creator is apparently moving to Chacha, I'm thinking of slowly transitioning to Chacha.