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