Trigger "Exposee all window" feature from command line

Hello I’ve been using a touchpad and i would like to trigger an alt tab menu from command line, so that i can bind it to a gesture.
I’ve tried using xdotool to emulate alt tab with no success (and the result would be finicky), and i’ve seen that using hot corners an “Exposee all window” rule exists.
I’ve tried to figure out what the call is but to no avail.

Any help?