Force currency for frontend completed order price, even if it is recalculated in backend

Hi,

I have set a default currency in USD and I want all my customers to pay in USD, but for bookkeeping purposes, I have to recalculate all the orders to BGN. And I can do that in the backend with your plugin, but when I do that the order price and currency are also changing in the frontend for the clients. I want the price and currency on the frontend to stay in the default USD currency. For the customer the price and currency should stay the same as they have paid initially.

Is this possible?