Usually I just brute force my way through by drawing even if I hate how it looks. Sometimes, changing my usual tools or brush settings really helps. Trying something new generally helps kickstart the mood. I know that’s not a lot, but I hope that helps even if just a little bit.
That said, if you’re looking for random prompts, try Shindanmaker. There’s a bunch of ‘em!
https://en.shindanmaker.com/c/list?mode=tag&tag=Drawing
Best of luck!