I've been playing SNES games online recently with something called Parsec, it's this free program that essentially lets you share your computer, and someone remotely connects as a second (or third or fourth etc.) player. They can use their controller, keyboard, mouse, etc. It's pretty rad, and the latency is impressively low if you've got good internet. Thought I'd share it with everyone, I actually used it to play NHL '96 with a friend just a few days ago.
https://parsecgaming.com/
It's way easier to set up than Hamachi etc, it just sort of...works.