See post #10 on this page:
https://f95zone.to/threads/ways-to-run-rpgm-games-on-mac.6056/
It only works with RPGM MV games that haven't been packed with Enigma. So, for example, it works just fine with Claire's Quest, with
Roundscape Adorevia, with
A Goblin's Tale or
Meltys Quest or the great new game
The Curse of Kubel (and countless of others, I should know, I've been using this recipe for the last two years), but it won't work for
Peasant's Quest or a couple of others
So, basically, all you need is
ANY RPGM game that works on a Mac; duplicate it, right-click to show package content and remove folder app.nw (inside Contents > Resources). This gutted out shell of a game (which you'll rename and keep) can then be used to run any non-Mac RPGM MV (not Enigma-packed) on a Mac, by transferring the www folder of said non-Mac game to where you found the app.nw (and renaming the www folder to app.nw)
Don't forget to edit the package.json file using TextEdit, and you're good to go