Instead of allocation on inventory, it's possible to allocate on supply orders which are created automatically upon creating a new order item. It's called direct allocation.
As an example the order in the image below has 2 items. The chair has a normal product allocation which will create a reservation in Clougistic. The prepacked item will be allocated direct.
Processing the sales order
a reservation will be created, to get this item allocated we need free inventory (purchase or produce this item)
no reservation will be created.
a supply order will be created (production/purchase) automatically upon processing of the order.
as there is a reservation the normal allocation rules apply (FIFO)
this particular item will be received for the order item in order 38748. It means that the inventory location will be assigned to the order item.
system will follow the zone sorting method.
picker will be forced to pick from the inventory location assigned during the receiving step.
To be able to process the supply order automatically it's import to have a supplier and supplier product for the prepacked item.