One setup, four inputs. 4 sessions on one screen!

Dell has a solution for you:

http://www.dell.com/en-us/shop/accessories/apd/210-ahsq

 I found a less expensive way to make 1 screen into 4! This device takes 4 HDMI inputs and displays it as one, two or four screens.

https://www.amazon.com/gp/product/B0732XM1Q8/

Here it is displaying inputs 1 & 2  stretched side by side. 

I will post pictures tomorrow of it displaying four Zwift setups!