Ask HN: Possible to play 2 player PC emulator games online?

I think the easiest way to do this is simply RDP. Have the emulator set up, open up RDP, and have them RDP into the machine. Then when you use the emulator map the player 1/ player 2 keys to whatever. It should work.

Many emulators have this functionality, called netplay. For example Mesen, one of the best NES emulators available:

https://www.mesen.ca/docs/tools.html#netplay

Also RetroArch (which has cores for many systems, including Genesis):

https://www.retroarch.com/index.php?page=netplay

FightCade2 is the most popular. Takes some work to set up, but has a lot of old games. No NES. Plenty of arcade though. There was Kaillera back in the day. I don't know where is stands now.

maybe https://parsec.app

Check out kosmi.io for nes and snes emulators in multiplayer.