Yes and no.
NetEdit queries for installed devices using a UDP/IP broadcast and broadcasts don't cross routers. DirectSoft also does when looking for unknown devices, but creates programming sessions using point-to-point addressing.
For NetEdit to configure an unconfigured device, it must use a broadcast. More specifically, we use a proprietary mechanism we refer to as an "addressed broadcast". The bottom line is that NetEdit and DirectSoft have different functions and behave differently by design.
That said, it would be possible to create a point-to-point connection from NetEdit...but doing so would make it possible to de-configure your device remotely, and leave you unable to reconnect. While most folks needing a remote tweek of ECOM settings would be willing to risk it, I am quite sure that Host's and AutomationDirect's technical support folks would frown upon giving such a nice length of rope to the customer base.
Alternately, the ECOM100 has a web interface that allows you to do many of the same things that NetEdit can do, and I'm pretty sure it will work just fine remotely.