I would like to know if there is a feature on Wave that could enable me adjust the exchange rate.
There isn't a way to change the exchange rate for a transaction at this time. We always use the mid-market exchange rate from XE.com for the day of the transaction. If that does not match your local exchange rate, you'll have to create transactions to adjust the amounts in your account so that they match what appears in your bank statement.
Thanks for your usual support.