Here is the full list of all 97 Divinity: Original Sin 2 achievements. It takes around 200 hours to unlock all of the achievements on Windows.
Complete the game in Explorer Mode
Complete the game in Classic Mode
Ascend to Divinity
Defeated the Kraken
Ifan: Forgive Lucian
Gain entrance to Lucian's Crypt without following the Path of Blood
Persuade Toyseller Sanders to give you his amulet
Defeat Adramahlihk
Lohse: Banish your demon
Obtain Anathema
Craft a grenade
Discover Reimond's Lair
Arrive at Arx
Enter The Arena of the One
Enter the Academy
Convince all party members to let you ascend
Pray at every altar on the Nameless Isle
Sebille: Serve the Mother Tree
Sebille: Destroy the Mother Tree
Sebille: Kill the Master
Arrive at the Nameless Isle
Craft a scroll
Awaken the corrupted Ancestor Tree on Bloodmoon Island
Learn of the Council of Seven's location from The Advocate
Learn of the Council of Seven's location from a higher power
Unlock your third Source Point slot
Escort Saheila outside without fighting the Lone Wolves
Take the ferry to Bloodmoon Island
Craft a skill
Set Gareth on a path of reconciliation
Shapeshift into every race
Correctly answer all of Crispin's questions
Receive Dorotya's kiss
Kill an enemy using Teleportation
Escort the Black Cat out of Fort Joy
Become champion of the Fort Joy arena
Serve Garvan the tainted stew
Become champion of the Driftwood Arena
Perform successful surgery on Natalie
Kill Andras, the necromantic dog
Adopt Peeper
Unlock your second Source Point slot
Help free Mari from the Voidwoken
Gain the Hero tag
Get caught breaking the law
Meet Meistr Siva
Arrive at Reaper's Coast
Escape Dallis' siege on the Lady Vengeance without killing every minion
Enter the Hall of Echoes
Take command of the Lady Vengeance
Welcome Tarquin to the Seekers' service
Defeat Alexandar in Fort Joy
Equip runes to all of an item's available slots
Kill Radeka
Use your first Source Skill
Face a higher power
Speak to an animal's spirit
Remove your Source Collar
Rescue Gareth from Braccus' Armoury
Arrive at the Sanctuary of Amadia
Flee Fort Joy for good
Escape the kraken's clutches
Arrive at Reaper's Eye
Win a persuasion event
Perform a successful theft
Force Dallis to retreat from combat in Fort Joy
Kill Slane
Escape Dallis' siege on the Lady Vengeance after killing every minion
Set Gareth on a path of vengeance
Learn of the Council of Seven's location from Malady
Lockpick your way into Mordus' hidden lair
Tame Featherfall
Destroy every Voidwoken egg in Reaper's Cove
Convince Alexandar to ally with you
Discover the hidden entrance to the Academy
Swear to the Covenant
Successfully walk the Path of Blood
Share Source with all of Rivellon
Purge Rivellon of all Source
Submit to the God King
Share Divinity with The Doctor
The Red Prince: Kill the Red Princess
The Red Prince: Become the father of dragons
Lohse: Embrace your demon
Fane: Return the Eternals to Rivellon
Fane: Embrace this strange new world
Ifan: Kill Lucian
Beast: Assassinate the Queen
Rescue Arhu
Make a deal with Adramahlihk
Beast: Ally with the Queen
Complete the game in Tactician Mode
Use the Curse skill
Gain the Villain tag
Successfully begin a match in Arena Mode
Successfully begin a Game Master session
Complete the game in Honour Mode