Soundwave on 20 March 2017
To be honest Pokemon for 2018 might make a lot more sense. The second fiscal year for a hardware is really when Nintendo likes to ramp up mass production, if they blow their wad all with Zelda/Mario/Mario Kart/etc. in year 1 there's not going to be a ton left for April 2018-March 2019.
Keep in mind too it's quite likely I think a deluxe port of Smash Brothers could be possible for the Switch this year too.
