User blog comment:Llama919/Anime: season 2 footage at the end of Shingeki no Kyojin part II: Wings of Freedom/@comment-121.96.238.63-20150627175449

I have seen the season 2 footage even the first time I saw the trailer. You know the part when Eren is battling Reiner in their Titan Forms, and Eren suddenly remembers during their Training days the moves that Annie showed(and did) to him. And then Mikasa challenges Annie to a sparring, with Annie saying "I wonder if It will work on a beast." That's it.

In short, look at the footage wherein Annie pounds Eren to the ground. That part should be included in the first movie. So you wonder why its included in the 2nd movie trailer, right?