I know if you were to take a streaming box and put it on your non-home network, it allows 2 streaming devices at max (i.e. if you wanted to bring the streaming box to a friend’s house and watch something on their TV); but if you were to create a site-to-site vpn and maybe also create the same Wi-Fi SSID at that second site, would it show the boxes are all on the same network?
It would be on the same network as long as your site to site VPN is set up properly. The wifi SSIDs don’t have to match.
That’s typically the purpose of VPN, to appear somewhere you’re not.
I have this set up with one of AT&T’s osprey boxes. Both sites have a firewalla, I have the osprey box set up to VPN to the home firewalla and it works flawlessly. You don’t have to worry about the SSID and VPN server does not need to be set up on the remote network either, just the home base.