Shinsengumi Imon Peace Maker, Sayonara ga Chikai no de Recommendations
Both manga revolve around the Shinsengumi. Peace Maker has quite an in depth story of the Shinsengumi, more so than Because Goodbyes Are Coming Soon, which only focuses on the teams last last dying moments. Both manga are also quite historically accurate, although in Peace Makers case it is balanced by fiction. The same characters also feature in both manga, and although they are of different interpretation, you can spot a lot of similarities. Both are outstanding manga and are definitely worth reading.