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