If you want to edit photos then Affinity is passable, and GIMP is a joke.

If all you want to do is draw, then Krita is a very capable alternative to Photoshop, but being good at only a specific subset of Photoshop capabilites doesn’t turn it into a replacement for it

Well the obvious answer would be all the professional Photoshop capable things man, we can love Linux and still admit there’s areas for growth