On the Items List within an Order, the Multi-Inventory products will be marked with the Multi-Inventory green icon. Also, you will see the list of the product's inventories used in the order.
On each inventory box, you will see the Cost, Quantity, and Total Amount for this inventory.
You can hide the list of the product's inventories by clicking on the Multi-Inventory Green Icon.
To view the inventories' details, click on the expand arrow icon located at the right of the Inventory Box.
In the Order Notes, you also can see the Multi-Inventories stock used.