Technically, mine would be Pokémon Picross and No Man's Sky, because I played them for about five minutes each last night before bed. So their combo game would be Skycross, a game in which I make pictures of all of the parts my spaceship needs to fly, and somehow have them in my inventory.
But for games that I invested time into, Overwatch and Fairy Fencer F: Advent Dark Force. I wouldn't know how to combine them though. Boy takes magical sword and fights the omnics that are oppressing his people.