Here is the full list of all 32 Dex achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Successfully used the Convince option in a dialog
Performed a headshot
Reached level 5
Completed the game
Showed THE Armagear hacker who's boss
Helped an old man off the street
Didn't leave anyone behind
Rescued Shen
Found Soto
Had a taste of all the 'professionals'
Bested a war machine
Reunited ill-fated lovers
Defeated an old acquaintance for the second time
Forced Mitchell to confront his past
Opened Ellie's eyes
Exposed Crash's identity to the world
Performed 20 Takedowns in a single playthrough
Picked 10 locks
Neutralized the TruBody gang
Reached level 10
Reached level 15
Acquired the laser gun
Installed 7 implants
Maximized a Major skill to level 6
Upgraded a software to its maximum level
Sold all the antiques to Hank
Opened the safe in the Aphrodite
Opened the safe on the Eclipse
Met the new BiofarmTech receptionist
Met the original
Drank more than 10 Energo Colas
Got crushed by an elevator