I have all sorts of color chickens in my flock including black ones and they still have attacked multiple times. They don’t seem to go for the black ones themselves (maybe because they’re also much bigger than the other birds ??) but they don’t deter them from attacking the others, at least in my experience.Some people hear suggest big black hens. They look like ravens to haeks, so they'll leave them alone
Humans also don’t seem to deter ours because I’ve had them swoop down or sit in a tree even if we were outside. Although I am somewhat interested to try the sweatshirt/scarecrow thing just in case.