DOOM and Wolfenstein run on Unreal, an engine famous very being able to run on practically anything. Moreso than that, they aren’t CPU intensive games, they’re incredibly GPU-dependent due to relatively small, linear stages with a set number of enemies. Turn down the resolution, adjust some textures, boom- games looks worse but it runs at 20-30fps.

Watch Dogs 2 is a game designed with the PS4 and XBOX One CPUs in mind. There are very obviously a shit ton of NPCs, a large open world, and a lot of complex shit going on behind-the-scenes at any given moment. That is incredibly stressful on the CPU, and there isn’t much you can do to help alleviate that stress without entirely reworking the game. Drastically reduce NPC detail and background character limit, reduce/remove shadows. Yeah, you can do that, but that will only do so much. With a GPU-bound game you can basically just lower the resolution until you’ve got a blur of pixels, but you can only do so much with a CPU-bound game.

There’s a reason that even Assassin’s Creed Odyssey tanks in frame rate on the current-gen consoles. I can’t even imagine how impossible it would be to make Watch Dogs 2 run on Switch.