Magic Wormhole is probably what you’re thinking of. The live handshake requirement is definitely a limiting factor on that approach, but probably still worth do

Magic Wormhole is probably what you’re thinking of. The live handshake requirement is definitely a limiting factor on that approach, but probably still worth doing. Other options would be QR codes and registry services. The protocol team is looking at using the ristretto algorithms to derive “subdomains” which would reduce the amount of key sharing a fair bit