I am actually quite baffled that this hasn't come up more. The last topic created on this was 2014! I know we get several on Amazon due to people knowing how to manipulate the lax return policies. I was informed that the ability through Royal Mail is in process. That sucks... we're US based
Currently, I have to manually create an order and change the address to you. Of course, "Ship-From" address is also your address, so the Zones will be off for billing purposes. If you are looking to ship a replacement with return postage, you have to create 2 separate orders and then make sure your shipping department combines them correctly. We all know how that can go. I'd probably be better off just creating the label through the Carrier portal, printing it, and attaching it to outbound shipment.
I am no programmer, but I find it hard to believe this feature would be difficult. We're already integrated with the various shippers. All you should have to do is switch the XML addresses; the rest seems pretty standard within LW (add item, set shipping method, etc). I would think a simple check box within the "Exchange Booking" or "Return" section titled Create Return Postage would be sufficient on our end.
I can definitely see this method becoming a problem as we grow; it is prime for mistakes and cumbersome at best. Hope this can be looked into.