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