Write-back from Rate Quote is based on how you set up your Custom Write-Back fields for the Freight Cost, Ship Via and Ship-To Address fields. You can set up these fields to write back to the Sales Order when you rate a shipment or for both rating and shipping a shipment.
After clicking Apply on the Rate Quote screen, refresh the Sales Order to see the following updates to the Sales Order:
Carrier/Service
The Ship Via field will be updated with the Carrier/Service.
Freight Cost
The Freight Cost will be written back to the Freight Cost field on the Totals tab of the Sales Order.
Ship-To Address
When the address is changed in StarShip Rate Quote, the Override flag is enabled and the address from StarShip is written back to the Shipping Settings tab > Ship-To Address on the Sales Order.