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