I'm currently struggling heavily with generating and handling encrypted secrets with friends and family (as part of inheritance planning treasure hunt).

Non technical people need a secure always offline device on which they can encrypt and decrypt info with symmetric AES and asymmetric public key tools.

They don't at all get the need nor the tech.

Would be nice if a verified nostr client could be installed via USB/SD on that always offline computer, and then be used to symmetric or asymmetric encrypt/decrypt text and files with friends and family.

Separately, trying to insist they chat with me over signal or simplex or heck any other encrypted messaging app...before we really need it...

Sorry, not sure if any of that is relevant to your request :(