Switching to OpenGL from Direct3D fixed it for me. I can still look up that stuff up if you guys want?
If possible, yes, I would like a copy of your save file, this may need further investigation...
I was having frequent crashes with Paper Mario too, but turned out when I switched from DX12 to OpenGL, the crashes stopped. So in my particular case, the game doesn't seem to wanna run fine on DX12. Glad the same worked for you.