Bad Usb with ALT-code and holding key option

I tried to add a holding key command and ALT-code to the P4wnP1_aloa (this avoid the need of using a particular keyboard layout).
Ex:
Hold left_alt key
Press numpad_1
Press numpad_2
Press numpad_3
Release left_alt key

Is it possible to add this feature to the bad usb of the flipper zero?