Here is the owner's manual:
Look on page 234 under "Recreational Towing". Is your Edge FWD or AWD?
According to that page you can tow them 4 down (both FWD and AWD) in addition it also states that the FWD version can be dolly towed. It even mentions either engine (2.7 Ecoboost or the 3.5L V6).
My parents had an older Edge (2009 I think it was) that they flat towed all over the place with their motorhome.