Underwear / shorts for lifting - need advice!

I have been looking for some boy shorts style underwear to wear that hold in my butt without cross-cutting my cheeks or flattening my butt. I don’t want them riding up my butt when I squat or disappear inside my butt, or else I’d just wear a thong. What do people wear?

I’m considering just getting some of the short shorts that women wear in the gym and using them under my pants instead of underwear. They seem to do a good job of staying in place without flattening your butt. Just so long as they don’t go up between my cheeks! I don’t care for the high waisted / tummy control but it would be fine if it did what I needed otherwise. No front seam! That doesn’t sound comfortable.

My Google and ChatGPT searches are not helpful - need real advice from other women who lift and get what I’m talking about.