Rate is already there, but to be useful we need the conversion fee as well.
At the backend, we can only request the products in base price, and at the frontend we want to convert them into the presentment currency. We use a react app in an iframe, so we cannot use the price formatting that comes with liquid templates. What we do is that we pass the rate to the iframe, but we also need to pass the fee, to be the price exactly the same as in other pages.
