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