Hello,
If you protected only folders on your startup disk then all Espionage related files are in one place, this is your home folder/Library/Application Support/com.taoeffect.Espionage3
This is the folder you have to copy onto the new mac before you launch espionage for the first time (if you launch it before that, it is no big deal, the difference is only that if Espionage does not find this folder on startup, it will take you through setup process and create the folder, then you have to quit Espionage and replace the newly created folder with the one from your old mac)
To reach that folder through finder, you hold the option key and select Library from the Finder's Go menu, once inside Library folder the further subfolders are normally visible.
Considering you launched Espionage already, then there will already be a com.taoeffect.Espionage3 folder. Quit espionage, rename that folder and then copy the one from your backup/old drive over.
Then launch Espionage and your folders should be there,
Let me know how it went,
Zsolt