Here is the full list of all 29 Hotline Miami 2: Wrong Number achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Unlock all achievements
Finish the game on hard mode
Kill 50,000 enemies
Clear all of the Writer's levels without killing
Get the big picture
Shoot two enemies during a chainsaw finish
Unlock THE ABYSS
Meet up with the Biker
They won't reach the Nuclear Throne
Clear the 1st floor of NO MERCY with the silencer
Finish the game
Get A+ on all levels on normal
Clear a level with each of the Son's techniques
Use every weapon in the game at least once
Finish SUBWAY without the Gang Leader seeing you
Clear a level with each Fan
Perform a 20x combo
Finish HOMICIDE without using guns
Clear a level with each snake mask
Destroy 100 electronic devices
Do as the Director says!
Perform a 15x combo
Unlock all of the Son's techniques
Unlock all weapons for the Soldier
Unlock all snake masks
Die 1000 times
Perform a 10x combo
Unlock all the Fans
Perform a 5x combo