So no. It most certainly couldn't have been done in another engine, because other engines cannot reproduce the stylized graphics, that make it work.
I'm sure we'll see similar style games pop up soon. It never fails, someone makes a cool game and a bunch of people rush to clone it's style.And it IS the vision. I didn't say visionary. They had a vision for a great game and they executed it perfectly. Which included a graphics style similar to The Incredibles movie. They had a great vision of the end product and they achieved it.
Personally I love the game. I haven't had time to play it as much as I would like to but so far, I've been playing the Demolitions guy. Nothing like spraying bombs on the enemy ramp and blowing em up when they run out!!!