Here is the full list of all 33 Mitsurugi Kamui Hikae achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Clear Inferno difficulty
Clear Very Hard difficulty
Complete all upgrades
Perform 10 Flourishes
Collect 100,000 SP
Clear Normal difficulty
Defeat 1000 enemies
Clear Easy difficulty
Clear Hard difficulty
Defeat stage 5 boss "Magatsu Suzuka" (any difficulty)
Defeat stage 6 boss "Magatsu Hino Tsurugi" (any difficulty)
Perform 10 Counters
Perform a Flourish
Max out Katana Gauge
Defeat stage 4 boss "Magatsu Kaina" (any difficulty)
Perform 10 Just Guards
Defeat stage 3 boss "Suzuka" (any difficulty)
Perform a Counter
Max out Life Gauge
Defeat stage 2 boss "Kaiser" (any difficulty)
Use Zanshin to defeat 50 enemies
Use Zanshin to defeat 100 enemies
Perform a Just Guard
Defeat stage 1 boss "Kaina" (any difficulty)
Defeat 100 enemies
Watch the tutorial
Defeat 10 enemies
Use Zanshin to defeat an enemy
String 50 hits
String 100 hits
Perform the holy technique "Celestial Judgement"
Perform the holy technique "Divine Wind"
Reach "Mitsurugi" zeal level