Yes, I have four running but there is some overlap as at least two of them have the same portraits in them, because of that for myself I'm merging them to prevent the overlap. But I'm new to the modding side for starsector so I don't know how exactly the game handles loading the different packs but I do know that the images do load in for the factions and for you to choose from at character creation. As long as the portrait packs have the appropriate faction files made.