Here is the full list of all 40 Attack on Titan 2 - there are A.O.T.2 achievements.
Completed 50% or more of the Scout Missions.
Completed your first Dire Elimination.
Completed the final chapter in Story Mode.
Leveled one character to max friendship.
Maxed out all training.
Saved 100 or more comrades.
Completed Story Mode Chapter 5.
Maxed out Titan Research Room level.
Completed Story Mode Chapter 4.
Completed Story Mode Chapter 3.
Reached 50% Gallery completion.
Eliminated a total of 1,000 enemies.
Built 100 bases in battle.
Used more than 100,000 RegimC40ent Funds in total.
Had over 100 allies die.
Completed 100 Side Missions.
Completed Story Mode Chapter 2.
Had over 100 allies join.
Completed 25% or more of the Scout Missions.
Reached 25% Gallery completion.
Completed Story Mode Chapter 1.
Eliminated a Titan with the Hook Drive.
Successfully completed a Sneak Attack.
Increased friendship rank.
Used a Buddy Action.
Achieved a Battle Rating of S in any episode.
Got selected as the top performer during training in Episode 1 of the Story Mode prologue.
Acquired all trophies.
Completed all Scout Missions.
Achieved a Battle Rating of S in all Story Mode episodes.
Completed all Story Mode Dire Eliminations.
Reached 100% Gallery completion.
Leveled the protagonist to max level.
Leveled one character to max rank.
Unlocked all characters.
Avoided 100 Titan attacks.
Got 2,000 total body part destructions.
Leveled all characters to max friendship.
Sent 50 gifts.
Used 1,000 Wings of Freedom.