I use big tire feeders, placed in the center of the paddock. These are BIG tires, off logging equipment, skidder tires. They are 6 feet wide, and 2 1/2 feet high. I cut one side of the tire off, to make a LARGE tub, with the top corners intact to help hold hay from being thrown out of the tire. I have two horses in each paddock.
When you have a few horses co habiting, there is always a pecking order. One horse is dominant, and the other is the underling, as you have already seen with your two. But with the BIG tire feeder, the weaker horse always can keep the tire between them, uses the tire for protection from the more aggressive horse. It works well for my guys. The tire feeder CAN also take a round bale, and hold it from being stomped and peed on, but normally, I just fill it with loose hay peeled off a round bale twice a day.
These tires are free to acquire from tire stores that service logging equipment. They will load it for you, onto your truck. You will likely need a tractor at home to unload them, and move them into the paddock, because they are very heavy. You can cut them with a number of different saws, chain saw, or my favourate, a reciprocating saw. Drill holes in the other side, the bottom side, so that any rain water that gets in there can drain out. Also will hold a TM salt block in the bottom channel, and give it enough protection from rain. Put this tire feeder OUT in the middle of the paddock, away from any shelter that the horses might have access to. They go OUTSIDE to eat, and come INSIDE to get out of weather. Less competition when in a confined area.
It will likely take a few days for your two horses to work out personal issues between them in their new home.