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