Check about this project https://miralab.io/MIRA_Technical_Specifications_for_platform_development.pdf. They suggest to store store different types of cryptocurrencies in one file calling Mirabox. You download this file with your money, and then it’s off chain, then you can put a file on a usb drive or send it via email or messenger to someone, there’s no record about it anywhere and also no commission. Looks great!