Red flag: "Sharedrop does not work with VPNs, please deactivate any VPN a device might be using"

Something better exists and its called the Magic Wormhole protocol

Flying Carpet looks interesting too https://github.com/spieglt/flyingcarpet

nostr:note1zx27zp9tktchk3mwhu8gjfy8wk5q3f9ud7aqxk2vdu827c5y9lysf6vmdl