Hello Jenn, and thank you for posting to our community.
Currently the ShippingEasy app is only able to pull in discounts per order, not by individual SKU's.
This means, that any SKU(s) listed in Customs forms will display the pricing information listed in your Product Catalog in ShippingEasy, or the initial SKU price sent from Shopify with the order.
If you need your Customs forms to auto-populate the discounted purchase amount, we recommend either editing the declared value for your products in ShippingEasy using the steps here: How to: Edit Product SKUs, or overriding your customs forms manually using the information in the link below.
That being said, because our Feature Request forums are monitored by our CEO and Product Team, they have considerably more influence over the course of our development.
Would you consider posting your request for discounts to be displayed by SKU to our Feature Requests forums?
The more interest they see for certain features there, the more likely those will be prioritized and added to our app.
Thanks again for your post!