Blog Post
How does Commerce handle transactions across multiple currencies?
Commerce takes the sting out of accounting for international sales by associating currencies and exchange rates to each transaction as they are presented by the upstream provider. Upon export, currencies and exchange rates will be displayed with the necessary transactions within your accounting file.
When not provided by the upstream provider, Commerce will apply an exchange rate to each transaction based on that day's historical average.
Alternatively, at your request, Commerce can deploy custom Advanced Mappings that allow your transactions to be routed to specific accounts created for each presentment currency.