No. While you can use alternative zip codes for domestic labels, there is currently a limitation that prevents ShippingEasy from offering the ability to use an alternate ship from zip code for international labels.
Of course, we'd love to hear if our shippers are interested in this feature. Feel free to post to our Feature Request Forum!
How to: Set different zip codes for my Return and Ship From Postal Code
Can I ship from my location, but have the return address say a different organization?
How is the Ship From address assigned to my orders?
How should I enter my return address to ensure that it gets validated properly?
How to: Set up International Shipments settings