Third-party "CD Key" sites may list "UFC 4 PC" to attract traffic, but these products are either console-only keys (PS4/Xbox) or complete fakes.
While PS4/Xbox One emulation is still in its infancy compared to older consoles, some high-end emulators are making progress. However, UFC 4 is currently not playable at a stable frame rate on any emulator, and this method requires a very powerful PC and a legal copy of the game. What to Look for in UFC 5 Ufc 4 Activation Key Pc
If you already own the game on a console, you can use the PS Remote Play or Xbox app to mirror the game onto your PC screen over your home network. Understanding Activation Keys and Scams Third-party "CD Key" sites may list "UFC 4