When using the API and query a currency column, you get a proper ISO currency code. ie “USD” for dollars “JPY” for Japanese Yen. That is to say that under the hood Coda already supports all currencies. It’s just unfortunate that a decision has been made to not expose these in the UI.
I use Chinese Yuan a lot, and while I can get the visual “¥” in the UI, it’s comes through as “JPY” (which shares the same symbol) in the API.