That's an interesting point actually. FE Warriors will likely be published by Nintendo in the west but it seems like the Rabbids game is Ubisoft publishing. So that would be two non-first party published games (in some regions) for two months around the fall. I'm betting we'll see another couple first party titles announced for then.
If they really want to hammer down the Switch having a steady flow of quality software there needs to be a few more games in those months. Smash so soon after ARMS doesn't make all that much sense. I guess Pikmin on top of Pokemon Stars could work.
I would say they still need one or both of these:
- A strong multiplayer title
- A casual game - 3D mario is not enough, all the other speculated games are way too core focused
Pokemon Stars could be that game, for both, although casuals don't often use the multiplayer functionality afaik.
If we go by Shikamaru Ninja's
first party thread we can see which teams might be able to release something:
Bolded = the ones who might show something "new" (not announced) this E3
(I am aware that some of the EPD teams are flexible and aren't totally locked like other studios are.)
EPD1: Mario Kart Deluxe / ARMS
EPD2: Splatoon 2 / Animal Crossing Switch
EPD3: Zelda BOTW DLC / New smaller Zelda title
EPD4: this is interesting, as their last game was Mario Maker. They are often the 2D mario or pikmin team... I can see them having something this E3 (they didn't do mario maker 3DS btw)
EPD5: Helped with Starfox and Tank Trooper. Certainly on a new project. Manager of this team is
https://en.wikipedia.org/wiki/Tadashi_Sugiyama
EPD6: Miitopia & 1-2 Switch - currently surely working on a casual title, but maybe too soon? Unless it's the Miitopia team led by Yuichiro Ito (brain training)
EPD7: I expect a new rhythm Tengoku from them. Could be this year as their last game was early 2016 and it are smaller titles
EPD Tokyo1: Hard to tell, did the louvre project for DS, might be on to something but I don't expect a big game surprise. Probably helping with Mario
EPD Tokyo2: Mario odyssey. I expect 2 player co-op announcement at E3. Maybe even online co-op. Pure speculation ofcourse, but the switch is made for 2 player games.
NST: No announced projects. Last was Mario Maker 3DS port - maybe Mario Maker Switch port? Or another game/port?
ND Cube Mario party team.. Mario Party switch?
Monolith Soft: Xenoblade 2.. That should keep them occupied.
Retro studio: Ofcourse, but I think 2018 is a safer bet for release.
HAL: 2 kirby 3DS games
IS: Fire Emblem, Fire Emblem, Fire Emblem (and maybe wario ware?)
Camelot: just did mario superstars, so unless they port it, I can't see them releasing anything soon
Game Freak: Let's assume Pokemon Stars

Grezzo: Ever Oasis
Next Level games: Luigi's Mansion? Last game was the fan favorite Federation Force
Tantalus Media: They are rumoured to port another Nintendo game to Switch..
And then there are a lot of smaller unknowns who were usually making eshop titles or 3DS games, but aren't known for their big console releases:
Creatures: ???
Alpha Dream: ???
Arzest: ???
Chunsoft: ???
Genius Sonority: ??
Good-Feel: ??
Grounding: ??
Indies Zero: ??
Jamworks: ??
Jupiter: ??
Probe: ??
Skip: ??
Syn Sophia: ??
Valhalla Games: ??
Vanpool: ??
Vintei: ??
Other 3rd party collab teams include Namco Bandai (Smash) and Platinum (Bayo 3

), Koei Tecmo (Fire Emblem Warriors) and Ubisoft Paris (Mario & Rabbids kingdom Battle)
^ HAL is making two Kirby games for 3DS.
Updated!