PC version Fans have made a PC version. Some are still early, so read the project page first.
Fans took Midnight Ghost Stone: A Native Metal Gear Solid apart and rebuilt it so it runs natively on a computer, often with widescreen, higher frame rates and mods. Here is the project we know about:
Midnight Ghost Stone: a native Metal Gear Solid PS1 recompilation with original-asset Vulkan presentation. Experimental alpha.