I'm having the same problem actually. I had to remove the largest male of a pack of 4. He won't let any of them eat. He even won't let the next largest come out of hiding. I started to see damaged fins and scales so I pulled him out and put him in a separate tank.
This is my plan. I've added a large school of dithers in with him. Kept him alone with the dithers for a week. I fed him very well hoping to teach him that food is very abundant.
The others I've been feeding frozen blood worms, flake food, sinking pellets. Things that float or sink very slowly and would be very hard to hog or stop others from getting to. I made some small changes to the tank by adding new plants removing some of the old ones I didn't like. Just to change the scenery. I added the bully and the dithers back last night and plan to continue feeding food that is hard to hog and protect for a few more weeks or as long as it takes. I'll let you know how it turns out.
Ohh ya. The dithers I just added to be a distraction during feeding and aggressive chasing.