What is the correct method for reshipping a returned order using Shipstation V3?
With V2 I simply click "Restore" on the existing shipment then create a new label.
With V3 "Restoring" the order does not work because all products are removed from the order and cannot be manually added to the newly created shipment. This won't work for international shipments because the packing slip and customs documentation will be empty and it will be rejected by customs.
How am I supposed to be doing this?
I agree that the way V3 works is terrible. In your situation, it SHOULD prompt for which items are going to be reshipped. I mean, the function of selecting specific products is already there because you do it when you split a shipment or when you create a return. When you create a new shipment, it should first ask to select which items will be included in the new shipment. Then it should ask if you want to remove them from the first shipment.
Why? Sometimes the customer reports a missing item. Well, that prompts and second shipment and it would be nice to record the item in the new shipment AND delete it out of the first shipment. If the whole shipment got lost, you'll want to duplicate all the items to the second shipment and leave the first ones alone. I'm confused as to why Shipstation doesn't understand any of this. The whole team should spend a week at any shipping warehouse that uses their product.