Saving the best for last, Nintendo is the last conference before E3. From the sounds of it, their conference will be primarily on Switch games coming this year, but it wouldn’t be surprising if they announced games for 2019.
To start, If they have anything for the 3DS, they’ll probably have that first. An update on Luigi’s Mansion could happen with a possible release date. Other than that, an update on Mario & Luigi: Bowser’s Inside Story + Bowser Jr.’s Journey could happen. I wouldn’t expect a ton of new game announcements other than another remake.
As for the Switch, there’s going to be a ton of stuff announced. Details on Smash Bros. could consist of gameplay, a look into the character roster, different modes, and the release date. Having it come out around the same time as the online service would make sense, but I see it coming out in October or November. We’re bound to get official confirmation on Retro Studios’ game and if it’s a Star Fox game. If F-Zero is announced, that would be epic.
Besides Smash, updates on Fire Emblem, Animal Crossing Pokémon, Zelda, and Mario games are likely. The release date for Splatoon 2’s Octo Expansion and more details about Kirby: Star Allies and Xenoblade Chronicles 2’s DLC are possible too.
While a lot will happen on the first party front, third parties will be just as important. To get the obvious out of the way, an official announcement of Fortnite is likely with a release date around the same time as the online service. An update on The World Ends With You Final Remix among others are likely. Some awesome announcements would be ports of Red Deas Redemption, GTA V, Nier: Automata, and Monster Hunter: World.
Those are all the predictions I can think of. I’ll be at E3 and playing Smash Bros. on Thursday. I’ll provide as many updates and previews as possible.