Pants for those of us with large behinds?

Finding pants is never not a struggle. I carry a lot of weight in my behind and working out does not help. I wear between a 50-52 waist on jeans/khakis. Sweatpants are really annoying. Anywhere from a 2-4xl depending on the brand. I’ve tried DXL but their sizing is inconsistent. I have 2 pairs of true nation pants from them- one is a 50 and fits great and one is a 52 and doesn’t even pass my thighs. Pls help. I do physical labor outside I want some decent lightweight sweats/work pants that can take a beating and keep me flexible.