We track everything in our shop by UPC. Since our Amazon SKU's do not have the UPC in them it would be great if you could pull in the UPC from Amazon orders so that we have easy access to the UPC when preparing shipments.
Shopify and Shipstation both have a product field for UPC, but Shipstation does not import that value from Shopify. The API exists, and it would be simple to have this included. This would greatly help with reports and exports of shipping reports.
ShipStation needs to integrate with Woocommerce so that order variation AND their SKU/UPC's come thru for order packing and filling. Right now only the "parent" info is imported into SS, and that creates extra work and a high risk of error for the picker and packer.