Here is the full list of all 50 11-11 Memories Retold achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Collide with 20 ghosts or more
Unlock the forgiven ending
Unlock the grudge ending
Unlock the betrayal ending
Unlock the revenge ending
Unlock the sacrifice ending
Take a photo of the rifle on Kurt's kitchen wall in "The Pursuit", fire the same gun in "Peace"
Find all missing boys from your village.
Take a picture of Kurt in "The Collapse"
Pull the cart of crosses in the cemetery
Finish Vimy battle without dying
Don't collide with any ghosts
Find all the collectibles
Find all the collectibles from Part III
Threaten the soldier three times to learn the truth
Take all the apples back to Lucie
Unlock the lone avenger ending
Go home to Julia
Bring all four wood pieces to the oven
Find all the collectibles from Part II
Win all card games
Perform all moves in the Dance sequence
Score with the hidden football in Paris
Find all the collectibles from Part I
Save Lothar
Do business with Joe
Take a picture of Lotty in Vimy trenches
Avoid all the mines
Use all your photographic film in one chapter
See all the credits
Complete Part III
Unlock the peace ending
Choose to go and save Kurt
Listen to Barrett's tearful account of the lives lost under his command
Win at card game against the old ladies in the village.
Give some chocolate to a german soldier
Kick the football in the POW camp
Complete Part II
Get out of the church of Passchendaele
Cut the german communication
Help Daniel in Passchendaele
Cut the gas in Passchendaele
As Lotty, comfort the soldier under the tree
Catch a rat in the tunnels
Find the hidden food stash in the tunnels
Purr with Lotty
Complete Part I
Send two pictures to Julia
Use one of the lifts on Vimy Ridge
Explore Julia's Room