Here is the full list of all 33 OCTOPATH TRAVELER II achievements.
Returned dawn to the world.
Approached the end of your journey.
Completed Partitio's story.
Learned all EX skills.
Completed Castti and Ochette's Crossed Path.
Completed Ochette's story.
Completed Osvald and Partitio's Crossed Path.
Completed Agnea and Hikari's Crossed Path.
Learned all secondary jobs.
Completed Castti's story.
Completed Hikari's story.
Completed Osvald's story.
Completed Temenos and Throné's Crossed Path.
Completed Throné's story.
Completed Agnea's story.
Completed Temenos's story.
Dealt 9,999 or more damage.
Gathered all eight travelers.
Learned a job's divine skill.
Gleaned information from 100 townspeople.
Rode the ferry to a new land.
Learned a skill for the first time.
Embarked on a journey.
Acted at maximum boost for the first time.
Broke an enemy for the first time in battle.
Unlocked all achievements.
Traveled to every location on the map.
Defeated the netherworldly threat.
Finished all side stories.
Obtained all records.
Obtained all battle-tested equipment.
Brought along four townspeople at once.
Soothed or knocked 100 townspeople unconscious.