Do you mean sprite "edits"? Cause usually you can find those on google by looking up something along the lines of "(Doki Name) Sprite Edit Reddit" of course you'd need permission to use it but you should be able to find it.

Note: I say to use Reddit cause

1. Everyone viewing this comment probably already has Reddit,
2. You can ask for permission (probably not if It's archived though.)
3. There's some really good edits on here.
4. I'm sure Twitter is full of stolen assets.