how to simulate WAN traffic within a LAN

I am interested in testing a web server within a LAN with simulated WAN connection request.

I know that the easiest way is to use cellular data connection for the client WAN traffic, but are there other ways ? e.g., On the client computer do a port-forwarding to proxy server outside the LAN with ssh-tunneling. In this case, who can provide the proxy server.

If you have any idea I'd appreciate it.