We are facing an issue which sounds like something more and more partners and customers need a solution for:
Adding one or more sales orders created in D365 FO to a POS transaction and then add extra items to the same POS transaction. That is, we need to be able to combine sales orders from D365 FO with a POS transaction where we add extra items and only make one payment. This is not possible today, which makes the sales process at the POS slow and the customer needs to pay several times (one per sales order).

The need for this solution is crucial as most retails have an omnichannel retail strategy where customers can purchase items from websites, call centers and physical stores etc. Therefore, we want to enable retailers to quickly help customers picking up their sales orders, purchase even more items and only make one payment at the POS.

Scenario: A customer has placed one or more orders via webshop or call center and thus, sales orders have been created in D365 FO. The customer must pickup the orders at a physical store (delivery mode = Customer pickup). The customer decides to purchase more items at the store.

Solution proposal: The store cashier should be able to recall all the customers sales orders from D365 FO on the POS and, also add the extra items the customer found in the store to the same POS transaction.

Benefits: The store cashier will only need to create one transaction and the customer will only have to pay one time. The solution will both save time and money at the store, as the cashier doesn't have to create multiple transactions (one for each sales order), and thus, the solution will save credit card transactions costs, as the customer only needs to pay one time.