long story short, I bought FFXV long before I cared about Denuvo but never played it, the game got cracked but Square Enix still haven’t removed Denuvo from the game on Steam; now I don’t want to install Denuvo spyware, if I download the game from Steam, don’t launch it, and just overwrite the .exe with the one from a repack, am I in the clear? would it work? I’d like to get the achievements, otherwise I’d just install a repack
Fitgirl is a repacker, not a cracker so this really depends what kind of a release is it, so you’d have to test by yourself.
It should work when it comes to launching the game, I’ve done it before in the past. But in theory, it’s unlikely to work with achievements given how cracks tend to overwrite the steam api dll files and hooks, likely disabling achievements in the process as part of the crack.
Something you could try is to copy the steam dll files like steam_api64.dll from the original copy on steam to the cracked one and see if that does the trick.