Peer-to-Peer multiplayer games matchmaking solution

I have a single-player open-world game (To make it easier to understand, imagine a Minecraft type game) and now I want to add the possibility to invite friends to your games / maps.

So the game will become a peer-to-peer multiplayer game with one player (the one that started the game) being the host. So I do not need a dedicated server, but my issue is with friend invite. (Using IP address is out for many reasons) and I do not need anything complicated like switch host if it disconnects or anything. Just a simple way to invite your friends.

In order to invite your friends, you need some kind of matchmaking/room/way of inviting with a code or something. It has to be cross-platform and allows a way to send a link (through email, SMS or something) so that your friend just click on the link and voila! The TCP connection is made between the 2 mobile devices and then everything else is just TCP between them.

I looked at Photon, playfab, game spark and it is unclear if they give this option. All I see are “random matchmaking” and the like.

Also looking on the internet, I could not find any real answer to this.

Anyone would have an idea what type of solution I could use for that?