2D artist new to the 3D universe, looking to sell 3D prints

To put it in perspective, would you like it if someone took your 2D work, printed it, put it in a frame, and sold it online without compensating you? Would crediting you for doing all the hard work take the sting away?

The answer is NO, reselling assets, or their parts is strictly prohibited by both general royalty free and editorial licenses. If you want sell stock models, they must be your own creations, or you have to have explicit permit from content owner (be aware that by purchasing stock model, you are NOT becoming its owner, or co-owner). Crediting asset's author is not required by aforementioned licenses, nor that it could help you in any way. Long story short, if you want start selling stock models, you need to use elbow grease and produce original content and not kitbashing it from someone else's work.