Here is the full list of all 79 Nioh: Complete Edition achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
You have unlocked all achievements!
Equipped +15 divine equipment in all slots. (Excludes accessories.)
Completed the 20th plane in The Abyss.
Defeated Ganryu's Sasaki Kojiro using only Dual Wooden Swords. (Cannot use a Visitor/Companion.)
Destroyed all the destructible cannons in "The Sanada's Resolve."
Bathed in every hot spring in the "Siege of Osaka (Summer)" chapter.
Defeated Sarutobi Sasuke in the mission "The Siege of Osaka (Winter)" using only tonfa. (Cannot use a Visitor/Companion.)
Listened to Katakura Shigenaga's entire introduction in "The One-Eyed Dragon's Castle."
Used the mask of an ugly fellow to defeat an enemy.
Bathed in every hot spring from the Kyushu Region to the Omi Region.
Equipped the Kusanagi Tsurugi, Yasakani Magatama, and Yata Mirror.
Completed "The Grand Tournament" on Way of the Strong or higher.
Completed "The Master Ninja" on Way of the Strong or higher.
Collected all Kodama in the "Siege of Osaka (Summer)" chapter.
Collected all Kodama in the "Siege of Osaka (Winter)" chapter.
Collected all Kodama in the Tohoku region.
Acquired mystic art for the tonfa.
Acquired mystic art for the odachi.
Acquired mystic art for the axe.
Acquired mystic art for the spear.
Acquired mystic art for the dual swords.
Collected all Kodama from the Kyushu Region to the Omi Region.
Defeated all types of yokai.
Collected all the best materials.
Made a total of 60 requests at the blacksmith.
Became Ryunoshin the dung lover's best friend.
Completed 10 missions with NPC or in the “Yokai Realm with a companion” with other users.
Completed "The Last Samurai."
Collected all Guardian Spirits.
Destroyed all the Revenant contraptions on "The Last Samurai."
Completed "Resentment Unleashed."
Defeated the Onmoraki during "Resentment Unleashed."
Completed "The Sanada's Resolve."
Completed "The Sparrow Flies Again."
Completed "Scion of Virtue."
Defeated all of Sanada's Ten Braves in "Scion of Virtue."
Bathed in every hot spring in the "Siege of Osaka (Winter)" chapter.
Changed the appearance of an item.
Completed the mission "The Siege of Osaka (Winter)."
Used all the culverins in the mission "The Siege of Osaka (Winter)."
Completed "Hands of the Dragon."
Completed "Spirit Stone Huntress."
Completed "The One-Eyed Dragon's Castle."
Bathed in every hot spring in the Tohoku region.
Acquired mystic art for Onmyo Magic.
Seized all of Aoba Castle's three-storied keeps in "The One-Eyed Dragon's Castle."
Completed "Yokai Country."
Made two circuits around Japan.
Completed "The Queen's Eyes."
Defeated Derrick the Executioner.
Completed "The Demon King Revealed."
Obtained first divine item.
Acquired mystic art for the sword.
Acquired 40 gestures.
Completed "The Samurai from Sawayama."
Completed any mission while transformed into a woman.
Used a disguise.
Acquired mystic art for Ninjutsu.
Reached level 100.
Acquired mystic art for the kusarigama.
Completed "The Source of Evil."
Witnessed Tokugawa's forces head toward a decisive battle.
Met with Tokugawa Ieyasu.
Found Muramasa and brought him in.
Reached maximum proficiency with your first weapon.
Completed "The Demon of Mount Hiei."
Defeated the Nue of Mount Hiei.
Changed your hair style or beard.
Collected all fragments of the Hiragumo teakettle from Shigisan.
Communicated with a yokai 10 times.
Completed your first Twilight mission.
Completed "The Ocean Roars Again."
Lit all three evil-warding bonfires in Itsukushima.
Forged an item.
Confused an enemy for the first time.
Completed "Deep in the Shadows."
Bathed in first hot spring.
Reached level 10.
Completed "The Man with the Guardian Spirit".