This is a great video to watch in your situation.
Jinx the blue throat is showing his dislike towards another macaw in this video. He has no intentions on being friends with the one macaw. If you watch the body language of Jinx his dislike for the other macaw is very obvious. If your macaws are snipping at each other to this extent Iād separate them.
If your macaws are just snipping at each other because oneās been preening the other, and the one gets tired of it. Well thatās expected.
If you are feeling overwhelmed there are resources all over to teach you the macaw body language. Shelters are full of trained people that work with macaws daily. The macaws Iāve worked with are very loud in their body language.
It is a possibility that the one macaw that the previous owner claimed is nice was nice to that person. My macaw is very bonded to me, and insists on being with me every waking minute. He tryās to bite anyone else that cleans his cage, or feeds him. If I opened the cage door heād come out to attack that person for being anywhere near his cage (nest). I clean his cage with him out, and we have a lot of fun. That takes time to get that relationship. I had to work with him daily. Some macaws bond very strongly to their owners, and dislike everyone else like in my case. Anyone on here that has a parrot that is a one person bird knows exactly what Iām talking about. Itās something that can be worked through but it takes a lot of time, and effort.
Best of luck, I hope something here helps.