It is possible to generate good quality hands with Stable Diffusion with ControlNet. Here's a video talking about generating different hand positions from models created in Blender. There's also discussions about this on r/StableDiffusion.
https://www.youtube.com/watch?v=ptEZQrKgHAg
Now from personal experience, it's not as easy as it seems in the video. It still takes a lot of tweaking and many iterations don't come out well, but hands are definitely not an insurmountable problem.
I mentioned it in another response as well, but here's the original implementation repo for anyone interested: