The trophy list for Assassin’s Creed: Valhalla has been leaked ahead of game’s release on 10th November 2020. Although the list has been taken from the PS4 version of the game, it’s safe to assume that the same list will also be on the PS5 version.
The base game has a total of 51, broken down into 35 Bronze 
The hardest trophy in the game (besides the Platinum) is definitely Completionist All the Way!, which requires you complete all the territories, including finding all the 780 collectibles in the game (made up of 386 Wealth, 233 Mysteries, 161 Artifacts).
Assassin’s Creed: Valhalla Trophy List
Viking Legend (Platinum)
Win Every Trophy
The Sage Begins (Bronze)
Complete the Prologue
To England! (Bronze)
Leave Norway
Hard Choices (Bronze)
Complete the Grantebridgescire Arc
The Order Is Revealed (Bronze)
Complete the Lunden Arc
The Good Saxon (Bronze)
Complete the East Anglia Arc
Take My Hand (Bronze)
Complete the Cent Arc
Calling in a Favor (Bronze)
Complete the Suthsexe Arc
The Enemy of My Enemy (Bronze)
Complete the Wincestre Arc
In the Footsteps of the Gods (Silver)
Complete the Asgard and Jotunheim quests
As It Was Foretold (Silver)
Complete “The Prophecy” storyline
England Subdued (Silver)
Complete Hamtunscire Arc
Disorder of the Ancients (Gold)
Eliminate all targets of the Order of Ancients
Rampage (Bronze)
Complete your first raid in England
It’s Alive! (Bronze)
Create a Jomsviking
Tranquility (Bronze)
Complete a Standing Stone puzzle
Equilibrium (Bronze)
Complete 3 Cairn challenges
Old School Treasure Hunt (Bronze)
Collect 5 Treasure Hoard rewards
Skadi’s Hobby (Bronze)
Perform a 150m slide in the snow
Witch Hunter (Bronze)
Defeat one Daughter of Lerion
Equine Attack (Bronze)
Assassinate an enemy from your horse
Silent Viking (Bronze)
Assassinate 10 enemies in a row without triggering a conflict
Everyday Life (Bronze)
Complete 10 World Events
Overdesign II (Silver)
While on fire during a fight, kill 3 hard difficulty soldiers without breaking their shields
Completionist All the Way! (Silver)
Complete all territories
Row Rage (Bronze)
Ram and destroy 5 boats in under 2 minutes with your longship
We’re in the End Game Now (Silver)
Reach Power 280
Hidden Trophy (Bronze)
Continue playing to unlock this trophy.
Builder (Bronze)
Reach settlement level 3
Home Sweet Home (Silver)
Reach settlement level 6
Pioneer (Bronze)
Reach Vinland
Home Decor (Bronze)
Place an item on each settlement cosmetic spot
Not the Norse You’re Looking For (Bronze)
Successfully pass close to a guard in a distrust area by blending with a group of monks
Face My Might! (Bronze)
Equip 8 abilities
Ultimate Refinement (Silver)
Fully upgrade and enhance a piece of gear
Flying Eivor (Bronze)
Get thrown 30 meters away by a destroyer or a housecarl
Twinkle Twinkle (Bronze)
Release a firefly in your settlement
Archaeologist (Bronze)
Complete all Roman collector challenges
Orlog Champion (Bronze)
Beat all the Orlog players
Good Catch! (Bronze)
Catch a fish of each type using the fishing line
Full Mastery (Silver)
Spend your first Mastery point
Is There Anybody Out There? (Bronze)
Light the unlit braziers on Hadrian’s Wall
Slam Master (Silver)
Complete all the flytings
Caladfwlch (Silver)
Draw Excalibur from the Stone
It’s Not a Bug, It’s a Feature (Bronze)
Complete your first Animus Anomaly
Seahorse (Bronze)
Swim a total of 3km with the horse
The Hidden Truth (Silver)
Obtain all video fragments and watch the hidden truth video
Master Hunter (Silver)
Defeat all Alpha animals
Dreamcatcher (Bronze)
Destroy 10 Curse Symbols
Godly Reward (Silver)
Obtain Thor’s Helmet
Worthy (Bronze)
Wield Mjolnir