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