Apps can create orders for your customers and send them invoices from the Shopify admin or the Shopify app. The orders that your app creates on behalf of your customers are named draft orders. Draft orders are similar to the orders that your customers create for themselves. The draft order is converted to an order when the shop owner accepts payment for it.
If you use Shopify Payments with multiple currencies enabled, then you can send draft order invoices in your customer's local currency. Mark as paid, Mark as pending, and Pay by credit card options are available only in your store's default currency when accepting payment for draft orders. If you create a draft order invoice using another currency, and then you decide to use the Mark as paid, Mark as pending, and Pay by credit card options, then the currency defaults back to your store's currency.