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