There's an easier way that doesn't require for you to download two versions of the game, you just need the version you want to play and Ren'Py SDK, which is much smaller than a full game.
And as a bonus you can play any Windows/Linux version of any Ren'Py game when you already have Ren'Py SDK.
https://f95zone.to/threads/how-to-create-a-mac-version-of-any-renpy-game.3289/
The only potential problem with this method is that save files created by a game you ported to Mac with the help of the latest Ren'Py SDK
may be incompatible with the original game if the original game was created by using an older version of Ren'Py SDK.
This problem is avoidable if you match the version of the Ren'Py SDK you download with the version the game was created by. You can find that version number by opening log.txt file in the main folder of the game or, in case it doesn't exist, script_version.txt file in the 'game' subfolder.
log.txt clearly gives you the exact version of Ren'Py, script_version.txt just contains numbers. For example, if there are numbers
7 3 5 in the script_version.txt, log.txt would contain a line
Ren'Py 7.3.5.xxx
Download SDK that matches with the game's Ren'Py version:
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