The joy-con that came with the game can act as player 1's controller, and the pro controller can act as player 2's controller. So yes, it will function as a second controller. I have not seen a game on the Switch that cannot use a pro controller rather than a joy-con, but if in doubt check the back of the game case and near the bottom next to how many players the game allows it should show pictures of which controllers function with the game as well. Hope this helps.