I have never set up a remote connection. My phone and laptop have a VPN connection back to my home network, and Plex just works. My TV also uses a local connect

I have never set up a remote connection. My phone and laptop have a VPN connection back to my home network, and Plex just works. My TV also uses a local connection. I believe that the regular "external" connection requires a STUN server, so it will fail without Internet.