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