So emacsclient/emacs deamon work with a tty, basically emacsclient opens a tty and sends it to the emacs deamon and it uses it to send output/receive input, so you really need to be local there's no way that I know to forward a tty on the network.
So it seems possible with socat indeed, I'll have to give it a try :)
One problem that I see however is that emacsclient also forwards signals to emacs when the window changes size for example, I don't think that will work with socat
The local socket opened is used only for configuration between emacs and emacsclient see: https://github.com/emacs-mirror/emacs/blob/master/lib-src/em...