Full list of all 56 Tales of Zestiria achievements. It takes around 100-120 hours to unlock all of the achievements in the base game on Windows.
The base game contains 50 achievements, and there is 1 DLC pack containing 6 achievements.
Either on (at least) your 2nd playthrough or in Moderate (or greater) difficulty, win the final battle without retrying! If you're familiar with the game, why not start your first playthrough in Moderate right away? You'll earn more Grade than in Normal!