Though we still have three movies until the end of Phase 3 of the MCU, we stand on the edge of a brand new era for Marvel's behemoth movie franchise. There's a reason we've been primed to expect the culmination of the Infinity Saga to herald great change and speculation suggests that Avengers 4 may even be the end of Avengers branded movies. Or at least the episodic mentality that leads every Phase towards one, anyway.
So what comes next? Will Marvel truly deliver on their promise to make everything different? Will they abandon the principles that built the MCU to be such a success and get rid of all of their founding charactrs? It seems unlikely, so the reality is that we'll probably see a marriage of innovation and evolution of established brands with sequels and new properties forming the shape of Phase 4 (or whatever Kevin Feige decides to call the franchise's post-Thanos period).
Obviously, there's a good chance of the Fox Marvel properties debuting in this period too, but they still aren't under Marvel's control and it could take three or four years to even get them into shape to debut. So they may well be part of a longer play.
But which movies will we see follow whatever Avengers 4 does for the end of the first real era of the MCU?
We know it's coming - and that it represents a difficult prospect for Marvel and Sony because it needs to be marketed BEFORE Avengers 4's release (thus potentially spoiling the sequel). However they deal with that, we know that Spider-Man 2 (whose new subtitle has been revealed) is going to be the first Phase 4 or Era 2 (whatever you want to call it) MCU movie.
Vulture will be back and so will Michael Mando's Scorpion, who will be looking for vengeance on Spider-Man for his injuries and imprisonment will too. And on top of that, it's likely we'll get another villain - very possibly Mysterio according to rumours - who will be introduced on a trip abroad that Peter Parker will take with school.
It's set in stone, which is not at all surprising given the Sony/Marvel deal and the need for both companies to maximise profits from the temporary deal. Specific details will follow (and fairly soon given that it will be release just a couple of months after Avengers 4's release).