Apple has ended Application Loader support since Xcode 11 (Latest News - Apple Developer). The only way to upload builds to Mac App Store is to use Organaizer. The problem is that Unity doesn’t create Xcode project for Mac (like it does for iOS) and there is no way to export APP to Xcode/Organaizer.
Unity instruction is obsolete since the moment: Unity - Manual: Build and distribute a macOS application
I’ve found 3 workarounds:
- use old Xcode
- download old Application Loader version from official site (https://itunesconnect.apple.com/apploader/ApplicationLoader_3.1.dmg), I don’t know why this version is still available =)
- use command line tools (I didn’t try it): xcrun altool --upload-app --type ios --file “path/to/application.ipa”
Hope someone from Unity team will reach this problem. Good luck!