If you have a rooster it can ride the feathers off its favorite hen. I don't have anymore feather pickers but my rooster has 2 favorite hens. They will squat and slightly raise the wings in submission for him or for me. None of the other hens do that.
I had problems with a feather picker and couldn't stop it. After a while it's a learned behavior and the other started. I ate the culprit but then the others had already began doing it also. I sold that group of 15 and kept my other breed and incubated to increase my flock. I don't have any more...