Create two new mapped keys in your Always On keymap: Mouse ON and Mouse OFF.

Mouse ON:
* Hotkey = Tab (or whatever key you like)
* Hold any Keystroke Actions while Hotkey is held = Default (Off)
* Execute a step when the hotkey is = Pressed
* Step 1 = New Repeater State Action -> all other, check Mouse Repeat = Off
* Step 2 = New Repeater State Action -> self, check Mouse Repeat = On
* Step 3 = You can add a sound and popup text to signal that it is working. I added a green popup text "Mouse Broadcasting ON" that displays for 1 second, and plays a sound "Windows Battery Low.wav"

Mouse OFF:
* Hotkey = Tab
* Hold any Keystroke Actions while Hotkey is held = Default (Off)
* Execute a step when the hotkey is = Released
* Step 1 = New Repeater State Action -> all, check Mouse Repeat = Off
* Step 2 = You can add a sound and popup text to signal that it is working. I added a red popup text "Mouse Broadcasting OFF" that displays for 1 second, and plays a sound "Windows Balloon.wav"