Here is the full list of all 52 Ys: Memories of Celceta achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Acquired all achievements.
Conquered Boss Rush.
Conquered Boss Rush without a single retry.
Defeated a boss in Time Attack without taking damage.
Defeated a boss in Time Attack in thirty seconds or less.
Played extensively as Frieda.
Cleared the game on Nightmare difficulty.
Acquired at least one of every item.
Played extensively as Karna.
Restored all lost memories.
Completed the main story.
Filled out all monster details in journal.
Overcame Gruda's trial.
Filled out all material details in journal.
Mastered every skill.
Amassed one million gold.
Achieved five hundred Skill Finishes.
Enhanced a weapon or armor to its limit.
Opened every treasure chest.
Played extensively as Calilica.
Defeated a rare golden foe.
Defeated the ruler of the Great Forest.
Discovered every resource point.
Completed the Map of Celceta.
Successfully completed every quest.
Endured all of Zara's tickle sessions.
Purchased every piece of info from Mouse.
Opened the door to the Temple of the Sun.
Successfully used Flash Guard fifty times.
Acquired both halves of the Mask of the Moon.
Played extensively as Ozma.
Found all of Mishy's hiding spots.
Cleared all obstructed paths.
Arrived in the ruined capital, Elduke.
Befriended all animals.
Located the underground village of Danan.
Walked an extraordinary total distance.
Proved your skill as a merchant.
Reunited with Eldeel at the Tower of Providence.
Achieved one thousand Aerial Combos.
Played extensively as Duren.
Successfully arrived in the Primeval Lands.
Defeated two thousand enemies.
Successfully used Flash Move fifty times.
Resolved the polluted river dilemma.
Defeated Duren in one-on-one combat.
Solved the mystery of the missing villagers.
Achieved five hundred Excellent Kills.
Played extensively as Adol.
Discovered a settlement in the Great Forest.
Successfully rescued the trapped miners.
Began your adventure in Celceta.