Here is the full list of all 26 Hitman GO: Definitive Edition achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Complete all objectives in all chapters without using a single hint.
Complete all objectives in the St. Petersburg Stakeout Chapter.
Complete all objectives in the sixth chapter.
Play for at least 5,000 turns.
Get pushed 100 steps.
Complete all objectives in the opera chapter.
Complete all objectives in the fourth chapter.
Die at least 200 times.
Crush three enemies under a falling statue.
Kill 100 enemies using the Silverballers.
Get chased by three guard dogs simultaneously.
Kill 100 Pair (Grey) enemies.
Complete all objectives in the third box.
Kill 100 Patrol (Yellow) enemies.
Kill 100 Turning (Teal) enemies.
Complete all objectives in the second box.
Play for at least 1,000 turns.
Worn all three disguise types.
Killed an enemy by emerging from a Secret Passage.
Complete all objectives in the first box.
Play for at least 100 turns in a single level.
Kill 100 Static (Blue) enemies.
Kill 5 enemies at once.
Throw an object without alerting anyone.
Killed 2 enemies at once.
Used a hint, ignored the instructions but finished the level...