What is few English translations for 吃窩邊草?
Do you mean like 兔子不吃窝边草?

If so, you could try something like "Don't bite the hand that feeds you" or "Don't foul your own nest."

Colloquially (and if you want a phrase with more profanity) "Don't shit where you eat" is common and could be used instead.

Also, a proverb like "People in glass houses shouldn't throw stones" is pretty intuitive as well.