>But only the orders placed via nopCommerce are copied over to ShippingEasy.
I understood you.
ShippinEasy plugin waits for two notifications from nopCommerce:
IConsumer<OrderPaidEvent>
IConsumer<OrderCancelledEvent>
If your order was paid plugin sent this order to ShippingEasy.
Can you ask developer of plugin for Ebay add this code to its plugin?
//raise event
_eventPublisher.Publish(new OrderPaidEvent(order));
If your developed can't add this code you can use our plugin for reading orders from eBay.
We developed this plugin and tested it now.
If you don't want to use our plugin and can't change old eBay plugin you can send eBay order to ShippingEasy manually.
Open the order in nopCommerce in admin mode and select tab "ShippingEasy", Press the button "Send order".