The Alchemist in Bleach

Foreword: Due to issues with the Fullmetal Alchemist author, the setting for this book was adjusted after chapter 40. Alchemy was replaced by the power of the Shinigami system, and the Fullmetal Alchemist elements were removed.
Keywords: Bleach, alchemy, equivalent exchange, Zanpakuto, Kido Someone once said that the two most painful things in life are: being alive and having no money, and dying and having no money left to spend...
Now Ichiro has discovered something even more painful: to experience both of these things again...
Having transmigrated a second time, Tenshin Ichiro brought his alchemy skills to the Soul Society, where he successively invented mimicry Zanpakuto, mimicry Shikai, Zanpakuto Shinshin transformation, and the creation of a Soul King, among other wondrous alchemical creations, turning the Soul Society upside down.