Prosperous universe might fit the bill depending on how deep into economy sim you want to go. Beware that you have some limitations as a completely free player, that are removed (last I checked) after you’ve made at least one purchase. So think of playing “free” as an infinite demo.
It essentially (if I’ve understood things correctly) aims to replicate the behaviour of proton.
Works like a charm, I have a simple alias set up that will run almost any .exe - even installers and stuff. Only thing that hasn’t worked so far was my digital exam software (that is essentially a windows rootkit) because it couldn’t find the cursor images lol.
Planetary Annihilation, Warcraft 3 (at least pre-reforged if you can get a hold of an old copy), Unreal Tournament, Killing Floor, Battle for Middle Earth (1 & 2), OpenTTD, Simutrans, Settlers: Heritage of Kings, some of the older Wolfenstien games, Battle for Wesnoth, Warzone 2100, Teeworlds, Widelands