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