per user vm isolation with shared network

Greetings, I have two vm which I want to isolate per user, if I'm not mistaken, I can to that with per session uri. but I want to setup a virtual bridge so they will get connected with each other. looks like that if I define the network as system, it isn't visible in the session. is there a way to do that? if I define the same network in both sessions, will it work? Thanks, Dagg