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