That's already a reality for many companies doing international trade. Especially global special-purpose device producers from smaller countries. It's annoying with paperwork and dealing with "what price was actually paid at the time", but it's not new. They contract a team from X, do work in Y, source materials from Z, V, W, then pay local accounting and tax in their govcoin equivalent - which happens to be the local currency.
For day-to-day multiple local currencies check out the history of the Brazilian Real.
