Okay, so Andre isn't original either. That means, just off the top of my head, we have...
Outright Rip-Offs:
Min: Bitchy, flailing, screechy-voiced Celebi.
Cress: Extruded Manaphy. Depressed as Hell from having to deal with Min.
Cayenne: Anger Management Weavile.
Amdusias: Butch Rarity with musical note motif to make being butch Rarity less obvious, maybe.
Orobas: Horrible porno Pinkie Pie.
Cozmo/Bearrings: Narcoleptic Ursaring.
Every Single Turf Tiger Ever: They're just furry Inklings, PK, come the fuck on.
Um... Collaborations. Yeah. That's it. They're Collaborations:
Beleth: Original red Beleth designed by Exty. Dubiously improved upon by PK because not magenta, and dungarees and bowl cuts are 2MANRY.
Andre: Looks like nothing else PK has ever drawn and fits in not at all because she had a nonbinary boner for Pengo's art at the time.
Nymlus: Fetish OC created by some pervert who keeps throwing money at her for gooey, TOTALLY CONSENSUAL non-con.
Kid Neon/Scrapgoats: Whoever's idea this was, I think we can fairly say that by expanding on the concept PK has taken a great big :autism: dump all over it.
V3nom: Originally designed by teebsly. Obvious rip-off of Fame Monster-era Lady Gaga, so only about 10 years behind the curve.
I think that's pretty much every single character PK has ever focused on for any length of time at all, with the possible exception of Biff, Lily the Mary-Sue Cat, and characters like Alice and Jacklyn who are basically just Generic Furries #04 and #11 respectively. wow, and people give her money for this?