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