They'll definitely still make some appearances in the Microsoft/Sony conferences. I mean Ubi still do every year whether it's Far Cry or Assassin's Creed, they feature it in those 2 conferences aswell as their own.
Rise of the Tomb Raider will be a huge example to that, as it'll be MS's way of gloating that they have it exclusive for a while (plus it's always been them showing Tomb Raider since the reboot)
As for what they'll show in their own conference...Just Cause 3, Deus Ex and RotTR are the givens. Maybe something on FFXV, and what's to come in the future of FFXIV.
Star Ocean 5 and Dissidia are in the "possible but not as likely to feature this soon" section for me, it'll be great if they're talked about but wouldn't be surprised if they weren't.
As for KH3...they have to give us something, they said at the private KH2.5 events when they showed the early footage that more news would come this year, D23 Japan might aswell not be classed as this year when it's in November so leaving it all the news til then would be silly. So I'd expect something, even if it was "So here's everyone's new outfits for KH3!!". Though they could also say what that smartphone entry is here too.
This is getting my hopes up that it'll be playable at London Expo in October too.
They had KH3D playable at the May London Expo 2 months before it came out in EU, same can be possible for this one too since it'd be 2 months before 2.5's release.
As sad as it is that there's no multiplayer in Birth By Sleep, I never got to do multiplayer at all anyway on the original so to me this is just a nothing-lost-nothing-gained situation, so I'm ok with it.
I'm ok with this, granted that more would have been better, but it might be better if 2.5 takes more priority this year so it doesn't get overshadowed by anything else of KH3. Especially with the lack of news on 2.5 at all before these past 2 weeks.
And while the initial announcement was best suited to happen at E3 like it did last year, anything majorly new from now on is probably better saved for TGS and Jump Festa.
I have to quote this Tumblr post I found a couple of months ago:
"Okay, but if any fandom is truly terrifying, it’s the Kingdom Hearts fandom. A lot of us have been following the series since it came out in 2002 and we’re just so patient at this point we’re like ****in assassins. We hide in plain sight and when there’s an update we just lose our minds and everyone else just wonders what the **** happened while we tear the whole goddamn world apart out of pure unadulterated joy from a minute and a half long trailer."
Yep I say that's true no matter what length of stuff is shown.