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