See Rename Files and Import Tags from Files from the Mac Documentation. The relevant bit there is that macOS uses the forward slash as folder separator and Mp3tag for Mac follows this approach.
If your file path is
Fela Kuti/(1969) Fela Fela Fela/01 My Lady Frustration.mp3
a correct format string is
%artist%/(%year%) %album%/%track% %title%