Yes, you can also create shipping labels and return labels in Pickware without an order, for example for spare parts, samples, or a return without an order. You can find the function in Pickware Admin under Orders → Shipping labels: Click Create standalone shipping label or Create standalone return label.
In the dialog, you select a shipping method as a template or the carrier directly, enter the recipient, optionally from a customer address, and create the packages with products or custom line items. This does not change your stock. You can then send a return label directly to the customer by email.
If such a label later turns out to belong to an order, you assign it to that order in the overview via Assign to order. The individual steps are described in How can I create shipping labels and return labels without an order?.