Monster Hunter 4 has never been released for PC, so it has no PC system requirements. It came out on Nintendo 3DS. Released in 2013.
Running Monster Hunter 4 on a computer
There is no emulator for Nintendo 3DS that this site will point you at.
Games of the same series that run on PC
Monster Hunter Stories 3: Twisted Reflection
Monster Hunter Wilds
Monster Hunter Stories Remastered
Monster Hunter Stories 2: Wings of Ruin
Monster Hunter Rise
Monster Hunter: World
Where Monster Hunter 4 can be played
Platforms: Nintendo 3DS.
