They will eventually. After almost a year they stopped fighting

Time usually helps. I’ve introduced a fair number of cats to each other through the years and while some didn’t become best buddies they would adapt in time.

Though we always fed them separately as we had a long lived fat cat who was on a perpetual diet. I think removing food stuff helped, but if there is always food out it’s usually not as big an issue. We couldn’t do that because the fat cat would just gorge then.