I wanted to introduce the kids to Heroes of Might and Magic III so we could play some hot seat when it's raining over the holiday.

I use Mac, but found that there's an open source implementation of the engine called VCMI (https://vcmi.eu) that runs on Mac.

I bought the game for 9 euro on GOG (https://www.gog.com/en/game/heroes_of_might_and_magic_3_complete_edition).
Downloaded the offline back version and extracted the files using innoextract (installed with brew install innoextract) and followed the guide here: https://wiki.vcmi.eu/Installation_on_macOS

It worked! There's also a bunch of mods that's installable through VCMI. For instance one with orchestral music scores by the Heroes Orchestra: https://www.youtube.com/c/HeroesOrchestra?app=desktop