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