All these can be touched up if the maker is actually trying to put any effort into it.

But if they're just using diffusion as a stencil or editor, and they disclose the process... That's fine, really. That's more akin to extensively using photoshop.

I dibt think artist shoukd have to prove that though. Abd while im sure its pretty uncommon this would stop an artist sending someone else to a con to sell their works if they cant make it themselves.

Or would be fairly easy to spoof, maybe the guy selling AI can actually draw well enough to put a rough sketch down, or can pull someone elses vod as proof.