Redirect sockets to each other

I was wondering if something like this is possible. I need to exchange some data between two computers (each on different network and behind NAT routers) over sockets but problem is that won't be able to know IP address of other and also I will probably need to open port. My solution is to have Node server with static IP address that will accept incoming connections, wait for data from one socket and just send it to another. But is there any way to just redirect those socket to one another so server don't need to do any other thing like read and write to socket?

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