Hello @simonmaltby
Thanks for your interest in our plugin.
What you’re asking is outside the scope of a plugin like this. This is a simple plugin that doesn’t use any kind of API. It only presents bank accounts details for the customer to pay, depending on the settings you’ve given in the backend configuration. It doesn’t understand nor make any assumptions about bank details, orders, conversion rates, etc.
Think what you’re asking could be achieved with a plugin like Booster for WooCommerce, as it handles exchange rates in various ways, but still believe some custom dev would be needed. HTH.