In our country (Argentina), as in others countries in South America, the inflation and devaluation are constant.
Because of this, is common to create a Quotation in dollars but make the Sales Order and Sales Invoice in pesos (local currency).
In order to maintain the traceability of the Quotation > Sales Order > Sales Invoice, we need to have the option of changing the currency despite the previous document.
For countries in Africa it is very common to create sales orders in USD and also sales invoices in USD, then ( to make it more interesting) we issue a govt based tax invoice using govt authorized POS terminal in base currency (local currency).
We have to make an unrealized exchange gain / loss facility for such items so that it can be reported for accounting as well. We are already able to raise sales invoice in foreign currency and then receive the monies with converted rate to company currency.