There a two versions of the E100 know through games the most know is probably the World of tanks E100 but the one i made in this video is on that was likely to be build and can be found in War thunder
The Maus turret was too heavy to be used on the E100 hull(e100 total weight is 130 tons, Maus 188, there is a very big difference) so they opted for the world of tanks one(Henshel if I'm right)