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.
Complete all objectives in the opera chapter.
Get pushed 100 steps.
Kill 100 enemies using the Silverballers.
Die at least 200 times.
Kill 5 enemies at once.
Used a hint, ignored the instructions but finished the level...
Play for at least 100 turns in a single level.
Kill 100 Patrol (Yellow) enemies.
Complete all objectives in the fourth chapter.
Get chased by three guard dogs simultaneously.
Kill 100 Turning (Teal) enemies.
Crush three enemies under a falling statue.
Complete all objectives in the third box.
Play for at least 5,000 turns.
Kill 100 Pair (Grey) enemies.
Complete all objectives in the second box.
Kill 100 Static (Blue) enemies.
Complete all objectives in the first box.
Worn all three disguise types.
Killed an enemy by emerging from a Secret Passage.
Play for at least 1,000 turns.
Killed 2 enemies at once.
Throw an object without alerting anyone.