Wow, I wanted exactly this for crypto payments. I think it's much more user friendly than qr codes...

Also it would be cool to have this as a transport in nomadnet / reticulum. They are transport agnostic, you can actually print the encrypted message as a qr code, stick it somewhere and if you read it with a compatible app, it is the same as if you have received it over internet or lora.

Nomadnet / Reticulum is pretty amazing.