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