If the immediate effects of the Rapture occur as I have been suggesting, then shortly after these tragic effects transpire, key leaders of key countries will definitely gather together, probably somewhere in the EU, for a series of summits. There is no way of knowing any details of what the topics will be—and I imagine there will be many disagreements and arguments—but this topic of a new global government will probably be most immediate and foundational. Under this major topic they will likely discuss and seek to make decisions on a global currency.
For many years experts have been saying that IMF (the International Monetary Fund, formed in 1945, with 29 member countries having the goal of reconstructing the international payment system 1) intends to replace the dollar with SDR global currency, using block chain technology. However, recently many do not recommend this approach, yet still insist that a one world currency is coming and that it will be different from what anyone imagines.2
One on-line article I ran across indicated that the bible does not state that there will be only one currency. The author suggested that there may be ways to harness all currencies. He stated that already online transactions can take place using multiple currencies in most countries.3
So there may not be a need at all to have just one currency; nonetheless, many will probably insist that it is a good way to unify nations and to make all nations of the world feel as one.
1 Wikipedia, “International Monetary Fund,” at https://en.wikipedia.org/wiki/International_Monetary_Fund.
2 Martin Armstrong, “The Coming World Currency,” at https://www.armstrongeconomics.com/markets-by-sector/foreign-exchange/the-coming-one-world-currency/
3 Compelling Truth, “Will there be a one-world government and a one-world currency in the end times according to Bible prophecy?” at https://www.compellingtruth.org/one-world-government.html.