I started looking into this a while ago. A couple similar existing tools:
- https://playit.gg which is focused on games, but works for arbitrary ports. Doesn't give dedicated IPs but it's free. Currently uses a custom QUIC-based protocol as far as I can tell, but is transitioning to Wireguard.
- https://remote.it a more professional service. Probably offers dedicated IPs. Not sure what tech it uses under the hood. Probably most similar to the OP.
And if you want to setup something like this yourself, using frp can be a lifesaver if you don't know iptables well.