Literally. Like a two-player cocktail mode for multiplayer.
Imagine that you played Wii Party U. Now imagine the two-player table games, like Baseball and Foosball. With Switch, it would be even more perfect, since the opposing players would each have the joystick on the left and the buttons on the right. (You'd lose the shoulder buttons when they're attached, though.)
I know that Sushi Strikers is a quick 3DS port, but the local multiplayer on Switch is set up so wastefully. It's a vertical layout on a horizontal screen, with one player in the back. Cocktail Mode would be perfect! Both players could even use Touch Controls, physically fighting over the middle lane.
I believe that Mario Tennis has splitscreen local, but cocktail mode should also be an option. Ditto for ARMS. Yeah. And Nintendo could bring back the best part of Tetris DS: Push Mode! I can also imagine some awesome competitive head-to-head Pinball or Pong or Space Invaders-type game.
In conclusion, where's our Wii Party U port, Nintendo?!