Pirate Ship offers deep USPS discounts, up to 87% off, and a simple interface...

https://cashnuyn401.theglensecret.com/pirate-ship-for-etsy-sellers-what-do-reviews-say

Pirate Ship offers deep USPS discounts, up to 87% off, and a simple interface that’s perfect for sellers who mainly use USPS. But if you need DHL Express or prefer live chat support over email-only, Shippo might be a better fit