It lacks the soundtracks that make you so immersed in the show. Most of the characters seem to be at the setting for practically no reason. It's a movie where nothing important happens. So many things in My Hero Academia have meaning, but this movie isn't one of them. It's a poorly crafted OVA that only acts as an excuse for the final part of the movie.
As a movie, it's fine, but compared to the main series of My Hero Academia, this movie does nothing in it's favor.