For the bully?Ahhh. A little separation and pecking order reset?
Separation can work....or not.
Try it, but keep in mind that sometimes a bird will just not fit for a harmonious flock.
I got rid of a troublemaker a few days ago, wish I had done it a few months ago, things are SO much calmer now. She was not a bully, but a neurotic nest messer, would not leave the nests alone, spent hours pacing in front and in and out of them, emptying them of bedding and disturbing all the other layers. Her and a chronic weak shell maker should be back from processor today to make great pots of stew/stock.