http://yobi3d.com/ looks pretty interesting. I found someone had posted it on reddit in the gamedev subreddit. It searches a bunch of 3D model sites for models. I’ve successfully found a whole load of low-poly 3D pokemon for printing (eevee!), and other things.
Been chatting with the owner for a few weeks now, coming out of Thailand. Lots of potential in their site, they just need a mobile version and a way to search by license.