when you look at you kemper you can see the signal chain.
From the input button the signal goes through the A,B,C,D effect slots then through the Stack and Effects.
If you want the whole signal or Master signal (guitar -> stomps -> stack -> x -> mod -> delay -> reverb) on the Main output
you leave it on Master Stereo.
Depending on where you connect your delay/reverb unit you set this output to Stack (guitar -> stomps -> stack).
If you want to run cab simulation unit you should use the monitor output and use monitor cab off, so you get the signal
after the EQ on the monitor ouput.