I have an idea!

Huh? You prolly mean netplay!

Multiplayer is made possible by the various input plugins that excist.

1964 has netplay inbuilt with Kaillera. However, by it's own admission, netplay is useless online and a bit hit and miss over a network due to general issues with N64 emulation. Even if a "perfect" plugin was released that made PJ64 online play possible, the graphics plugins have issues with splitscreen play in many games anyway unfortunately.