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