I was wondering if anyone knows how to extract the textures for the paintings that Sims paint in-game with the easel. To give you an idea, I'm talking about the textures shown in here, the ones labelled "original". I already asked in the Sims4Studio forums a couple of weeks ago, but I don't think anyone knows how to. I believe the paintings appear in Sims4Studio with a blank thumbnail and when you try to clone it, it appears with no mesh and no textures, so I think the program may not be fit for such task. I'm more than willing to work with a different program than Sims4Studio (is S4PE still a thing?)
I am uncertain how to do it, but this may be a clue to help you. I have an overwrite pkg that I got long ago and I tried to add additional textures and couldn't. NOW I understand why, the overwrite pkg is just replacing the textures for the paintings. The clue is that the ids of the original painting textures are in the overwrite pkg.