You can use the solution below. We've been using for a year and so far
so
good.https://www.selleractions.com/services/amazon-order-update-on-shipstation
Hello,I'm using SellerActions for that purpose. They're importing
customized Amazon Order Data into ShipStation. Works for me very well
especially in busy seasons.
ShipStation overrides Customized Amazon Orders even though it is
transferred by a Third Party Application. However, SellerActions solved
that problem. I highly recommend their solution.SellerActions