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