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