What is involved in getting Unreal Engine to export a game file for MacOS?
He would need to have a Mac (or a VM), get the files on that system and build it there. The Mac dev ecosystem is really bad for people running windows and linux as you need to jump through stupid hoops for no real reason. Sadly apple restricts its users and developers alike :/. Its just a really big inconvenience to do, especially for people who don't know how to use VMs