My team is working on an MMO RPG game and we were concerned that if we make the game using windows computers that are running the windows editors of UE4 it will be incompatible with Mac OS.
You can develop the game on PC and create a packaged game for Mac. Part of the process does require a Mac, but you can rent one on the cloud for around $19 or buy a cheap one for that.
No it will not work. Windows exes are incompatible with macOS and vice versus. You need to build for Mac in order to use it on a Mac
I think it will be a little bit to play on another platform like Mac. Tell your team to make the game more friendly. So that the people can easily play using different Windows, Mac, or other operating system. If you need any kind of windows driver updates. This one you can try. All the best!