hi,
The setup is described in
# Used to listen for the player activating or releasing certain inputs.
# The input is defined by the *Input* option.
# Players can configure the key for the input in the Creative Input Actions section of the Keyboard Settings.
input_trigger_device<public> := class<concrete><final>(creative_device_base):
# Enables this device.
# An Input Trigger will listen for inputs from players that meet the device requirements.
Enable<public>():void = external {}
About line 1570 of Fortnite.Digest.Verse
See Fortnite Input Devices documentation
Players can find and rebind these inputs in the Creative Input Action section of the Keyboard Controls and Controller Mapping tabs in the Settings Menu.
Open the sidebar, click the gear icon to open the Setting Menu, then click either the Keyboard Controls or the Controller Mapping icons. You can find the Creative Input Action section of the settings by scrolling down the list in the left navigation area. This is where players can change which actions map to which controls. These settings apply across all of your Fortnite experiences.