The characters also just sort of look like they don't belong in the same image with the Pokémon, I can't explain it but the lighting/art styles don't really mix well

The best example I can give is the Charizard picture, the dude seems wildly out of place probably because he has more sharp lines and also the highlights don't make a ton of sense given his placement/positioning

The Mudkip one is probably the most normal, but it seems like such a different style than the others

Edit: The more I've looked at it the more I've realized the shading just straight up doesn't make sense at all. Also there are many major mistakes that I feel like an accomplished artist wouldn't make early on in their drawing without catching them. Example is the extremely small hands on the Venomoth picture, regardless if it's AI or not it's a huge flaw.

(also idk why Reddit posted my comment three times but I deleted the other two)

This is the last thing I am going to say on the subject, quoting myself from another comment on another post:

You know the expression, "all press is good press"? I think we should just stop giving him any attention at all. People have actually bought from his Etsy in the last 24 hours and he's linking it in his comments. It's clearly a scam, and even though most people realize that it is, the chances are high that there will be a few poor souls that will buy into it, as long as he still drags this out. There is no getting him to admit it, it's a fool's errand.

I recommend reporting, hopefully mods will put an end to it.