Soukou Akki Muramasa

https://vndb.org/v2016

In the first half of 20th century, Rokuhara Shogunate rules Japan with an iron fist of robotic suits of armor called Tsurugi, while the West wants to turn Japan into another military base. A policeman called Kageaki Minato arrives into a city of Kamakura to solve various different cases involving Tsurugi users (or Mushas), and when all other means are proven useless, defeats them with a skillful use of his own Tsurugi, the bloody red Muramasa. But he doesn't do that out of justice. He only wants to atone for his past sins and to defeat the most powerful Musha, one known as the Silver Star.