Here is the full list of all 40 One Piece Pirate Warriors 3 achievements. It takes around 100-120 hours to unlock all of the achievements on Windows.
Break through one Character's growth limit.
Complete the "Final Island" in the Dream Log.
Unlock all Characters.
Complete the Dream Log.
Use Hero Power at least 100 times.
Complete 15 or more islands in the Dream Log.
Obtain 20 or more Skills.
Complete five or more islands in the Dream Log.
Complete the Final Chapter of the Legend Log.
Obtain 100 or more types of Coins.
Defeat over 100,000 enemies.
Complete the Fourth Chapter of the Legend Log.
Defeat over 10,000 enemies using Special Attacks.
Complete the Third Chapter of the Legend Log.
Obtain 50 or more types of Coins.
Defeat over 10,000 enemies using Kizuna Attacks.
Complete 25% or more of the Gallery.
Increase one character's Crew LEVEL to MAX.
Complete the Second Chapter of the Legend Log.
Achieve 100% Legend Points in a single episode.
Obtain 20 or more Skill Posters.
Unleash a Special Bond Attack with four Crewmates.
Defeat 300 enemies using a single Kizuna Rush.
Complete the First Chapter of the Legend Log.
Use Kizuna Attacks of 3 different Crew mates in 1 battle.
Unleash your first Hero Power.
Change Crew members for the first time.
Obtain one Skill.
Get an S-Rank Results Evaluation for a single episode.
Obtain one Coin.
Obtain one Skill Poster.
Complete the Legend Log Prologue.
Unleash your first Kizuna Rush.
Unleash 20 or more Kizuna Attacks in a single battle.
Defeat 1,000 enemies in a single battle.
Unleash your first Kizuna Attack.
Obtained all achievements.
Achieve 100% Legend Points in all episodes.
Complete the entire Gallery.
Increase 20 or more character's Crew LEVEL to MAX.