How do I build "RLPlugin" on Mac?

Trying to build a project from a colleague in xcode 14.3.1 on a silicon mac pro m1 max for opening in UE 5.1.1.

Build appears to finish – no errors – but when trying to open in UE it complains about ‘RLPlugin’ needing to be built in IDE.

How do I get this to build in xcode?

The folder RLPlugin is inside Plugins