Yeah if you know the ip of your peer you don't need STUN/TURN from what I remember.
If it's ipv6, I think that's true. If it's ipv4, then you still have problems. They could be behind NAT or worse, CGNAT.
If it's ipv6, I think that's true. If it's ipv4, then you still have problems. They could be behind NAT or worse, CGNAT.