At the end of Avengers: Age of Ultron, we saw a new Avengers team being formed under Captain America's command "“ but that doesn't mean that the same roster will be kept for Civil War. In fact, in all likelihood, the allegiances will be changed on the course of the third Captain America film.
But how will that happen? Which sides will be chosen by the older and the newer Avengers? Well, we might have some pretty good idea.
Civil War "“ Captain America's team

As quickly as saying Civil War, we can count the team members which will join Captain America right on the spot. And these team members are Falcon, brought into the fold by Steve Rogers and Black Widow, with whom Captain America connected during the events of the Winter Soldier.
Speaking of which, Bucky Barnes is another team member which could join the Civil War on Cap's side "“ he is returning and, if he will have any part in it the ruckus, it won't be on Iron Man's side (since, well, he is responsible for the death of Tony Stark's parents). But is it really so?
Another expected team member would then be Hawkeye "“ while he could go both ways (so to speak), we know that he is strongly connected to Black Widow, with their friendship actually being mistaken as a love interest throughout the first Avengers film. So if Black Widow joins Captain America in Civil War, then Hawkeye will be there too.
Lastly, there is also Scarlet Witch, who has the most reasons to go against Iron Man "“ after all, she blames him for the death of her parents.

