This Artwork is Genuine, his original artstyle is apparently cartoony and has very round eyes compared to the others. Also tends to add alot of memeish, moeish and very guro based artwork.
The other works posted were intentional trolling by him to joke on AI plus Artist Block. He has since decided to delete it on the New Year 2023, decision not only by him, but by his fans and his friends (other artists) because they worry that he will get cancelled/insulted for taking on joking too much.
Edit: Best to request Approver to Remove the Bocchi and Finana, 100% AI. Adjust the setting of The Kyaru to add Collab + FroppyArts to it. And possibly add back the original artwork so when newer ones are added, hopefully not AI, people can recognise which is real and not AI, so they won't get banned.