We need to tag incomplete orders (back-orders) containing items with negative stock levels and after we also need to see what are the pieces missing in each order. We do not need to open every single order, but we just need to know what and how many pieces do we have to produce for the waiting back-orders. An important feature is the option to filter by date or by order number to keep some system in it. All this can be done by using export or having some page with a list of back-ordered items.
Our workflow in brief:
A customer orders for example leggings + sports bra. The sports bra is in stock, but leggings are not and we have to produce the leggings first, so the order has to wait until we produce the leggings, the order is complete and ready to be shipped to the customer. We need to see all the incomplete orders and the missing items (product variants) in the order administration.