"all the qualities of other instruments like banknotes but lends itself to electronic exchange"
I'm sorry, fiat currencies do not lend themselves to digital exchange ? Since when ?
The only time I have to use banknotes is when I'm going for pizza takeout at my friendly local pizzaiolo in his mobile kitchen.
The rest of the time, I'm using a no-contact VISA.
Apparently, you can also use your phone for paying stuff.
I can also send money to anyone with an IBAN number. I do that all the time when I have to pay an invoice for work done in the house, or an important delivery. Easy as pie.
The only thing I can't do digitally is give someone ten bucks (euros, whatever). To do that, I have to use physical currency.
If that is the problem they want to solve, I think it would be a lot more simple to have an app from the bank that you can charge, and via Blutooth you could sync between two phones for a given amount. End of problem. No need to go fabricate some more funny money for that.
Stop with the funny money already.