It should be noted that while several central banks are collaborating on digital currencies [1], all signs point to implementations not using distributed finance/ledger technologies or crypto/tokens/stablecoins. The ECB has specifically stated they will not tokenize or issue a stablecoin for a digital Euro [2] [3], and I would expect other central banks to follow their lead.
[1] https://www.bis.org/publ/othp33.pdf (Central bank digital currencies: foundational principles and core features)
[2] https://news.ycombinator.com/item?id=24686582
[3] https://www.ecb.europa.eu/euro/html/digitaleuro.en.html