Yeah I just learned about the field choosing thing. Very cool.
nostr:npub1xtscya34g58tk0z605fvr788k263gsu6cy9x0mhnm87echrgufzsevkk5s you could save it in the notes section of your contact card and share it using the option at the bottom.
When you share a contact card on iOS, you can choose what fields (including notes) are and are not sent. And you can even use AirDrop to share it wirelessly between devices.