But if you have a place honestly just continue doing it. There is always a buyer somewhere, just have to find your right audience.
In 7+ years I only sold 5 normal pieces and 1 nft. I wanted to sell this piece to local pizza place:

But when I came in I was embarrassed to ask money for it so I just gifted it away. I guess I am better artist than I am a seller.😛
Yes, Clip studio paint has 3D figures and poses. I have done a few pieces with 3D already(1, 2,3...)