In the past we've usually had a very clear path for the Marvel movies. The next four or five years lined up for us as we go forward. Right now though, that isn't the case.
Up until Captain Marvel, we have a solid idea of what is coming to the MCU, but after that, things get very foggy. There is a reason too. Speaking to the Toronto Sun, Marvel's Kevin Feige explained that Phase Four's films hadn't been outlined due to fear of spoilers. He said
Where we go after Avengers; what those 2020 films are, we're pretty sure what those are going to be… but if I tell you that, we're getting into spoilers.
Perhaps we can take away from that that those films will be reactive in some way to the events of the Infinity War, and the second, unnamed Avengers film. Here's hoping to some unexpected team ups.