I would like to have the option to trigger a macro on the release of a key as well as the press.

I'm currently playing Apex Legends and it requires you to manually switch to grenades before throwing them (right on d-pad) and to manually switch back to your gun afterwards with the quick swap button (triangle) unless you run out of grenades. The grenades are primed and aimed by holding the fire button, and thrown when it is released. I would like the ability to assign a macro to the release of the fire key that presses the swap weapon button so I can immediately switch back to my gun after throwing a grenade.

To take this idea a step further I would like to have the ability to assign a one shot macro to a key from within another macro. Since grenades are fired with the same key you use to fire a normal gun the, previously mentioned macro would require you to assign it to a separate key exclusively for throwing grenades. Otherwise you would quick swap guns every time you stopped firing. I would like to be able to set it up so pressing the grenade swap button assigns the previously mentioned macro to run once on the next release of the fire key and then have it revert to its normal behavior.