This also makes sense for fighting games, I once used a game engine called fighter Maker and there you could add as many collision masks as you needed, there were various types(not necessary for GDevelop, because the name of the collision mask would be enough) and the collisions could exists for defined periods of time, for example you could add various *hitboxes just for health in case you wanted to give a character “weak spots”, or move the hitbox for doing damage along with the fists and contact points of the attack, in that program the functons of each type of hitbox where predefined and colour coded but that made sense because the engine was for one specific type of game.
This could alternatively be worked around by using childs of a prefab as hitboxes, if my request was accepted, so I’ll link this request on that post.