I read an interview with Geoff Johns where he says that the Arrowverse and the DCEU co-exist in the multiverse. The Flash Movie actor Ezra Miller also teased this idea as well.
You can read the Geoff Johns interview here: http://www.cinemablend.com/television/What-DC-Calling-Its-Split-Universe-Why-Everything-Being-Kept-Separate-67994.html
I know that a lot of us are not the biggest fans of the DCEU, but you have to admit that it would be cool to make characters like Batman, Wonder Woman, Aquaman, and Green Lantern canon in the Arrowverse. I guess a problem could lie in the fact that characters from the movies and shows look different, but we all know that the Multiverse is known to mess things up (such as Henry Allen having the name Barry in the 90’s Flash show, which is canon in the Arrowverse since Barry saw it in the speed force...)
Maybe the fandom can create an Earth designation for the DCEU (Earth-99?) What do you guys think?