https://techcrunch.com/2018/06/12/super-mario-party-lets-you-connect-multiple-switch-consoles-to-expand-your-screen/

Super Mario Party is coming to the Nintendo Switch but alongside the new party gameplay, there appears to be an interesting new use of the Switch hardware for multi-player purposes.

It appears you’ll be able to modularly connect at least two Nintendo Switch consoles to expand the size of the screen you’re working with. In gameplay it seems actions will be able to seamlessly move from one screen to the other after users draw where the connection between the consoles are.