If Sweden can be able to do this, I believe it is not all other countries as you have put it that can follow suit, because many countries are still fall short of technologically and electronically know how. So, its damn not going to be an easy journey for them at all and even, most of them still believe though ignorantly in Fiat currencies for real other than any Cryptocurrency.
It needs a core rule where the regulations lies and backed up by strong foundation of knowledge on technology, But for now we can't say anything nor predict since we do have different government strategies. Not all country may survive without a fiat currency and may adapt changes towards the technological advancements we have now. I think if fiat currency will be obsolete, certain problems might happen specially on economic bases.