Background of the issue:
My WooCommerce store’s default currency is KWD, and I’m using WPML Multicurrency to offer additional currencies like AED, USD, AUD, etc. When a customer switches to another currency and completes the purchase, the order in WooCommerce and the generated invoice are both saved and displayed in the customer's selected currency instead of the default KWD.
Symptoms:
Orders and invoices are showing in the customer's selected currency instead of the default KWD.
Questions:
Is there a way to make all orders and invoices always use the base currency (KWD) for consistency in accounting, even if the customer checks out in another currency?
Is there a built-in option, filter, or recommended customization in WPML to achieve this?
I can see you have inquired about this in the past as well, unfortunately there is no feature at the moment that would do this functionality out of the box.