First, GMDX it's amazing.

Second, there's Open Deus EX (I think not GMDX compatible yet) and DX-Rust, which it is.

I still play to that game, and it's my favourite among Slashem and some few interactive fiction ones.

OpenDE: Fast, vanilla https://github.com/jarmitage99/OpenDE

DX-Rust: Slow, AI slop, but it can be improved. It supports GMDX https://github.com/Grissyelda/dx-rust

If you use Recomp Launcher you can install these with ease, even on Steam Decks.