While we've known for some time that there would finally be a sequel of some kind to the 2016 anime series Kabaneri of the Iron Fortress, the actual plot of the upcoming anime film, Kabaneri of the Iron Fortress: The Battle of Unato, remains mostly a mystery. A newly released trailer offers more insight into the nature of the film while showing off several returning characters and sweet flips and moves.
https://comicbook.com/anime/2019/03/16/kabaneri-of-the-iron-fortress-film-trailer/