The documentation says that you can manually call the action handling function of an action by using CallFunction, a RobloxScriptSecurity method that is also completely undocumented.
Current Documentation:
Bind an action to user input given an action handling function. Upon a matching input being performed, the action handler function will be called with the arguments listed below. Valid input enum items include those within the following: Enum.KeyCode, Enum.UserInputType or Enum.PlayerActions . Call this function when a player enters the context in which an action can be performed. When the player leaves the context, call UnbindAction with the same actionName. You can manually call the action handling function of an action by using CallFunction.
Page URL: https://create.roblox.com/docs/reference/engine/classes/ContextActionService#BindAction