The absolute minimum space you will need for these two launch monitors is 10'W x 9'H x 16'D.
QED and EYE XO are both placed overhead. The only difference in setup is that QED is placed 3' behind the ball whereas EYE XO is placed 3' in front of the ball.
But as far as spacing requirements go, it doesn't really change anything. You'll need between 7-8' between your screen and projector which puts your hitting area around 10-12' from the screen. You'll then need another 4-5' for your backswing.
One thing to note is that these units need to be between 9-10' above your ball. So if you have ceilings higher than 10', you will need to mount the launch monitor with an extension that drops the launch monitor within that range.