Here is the full list of all 36 Valkyria Chronicles 4 achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Obtained all achievements.
Obtained all decorations.
Watched all event scenes.
Obtained A ranks on all missions.
Obtained all tank parts.
Obtained all infantry weapons.
All of your classes were upgraded to max level.
Recruited all squad members.
Triggered a Last Stand 15 times.
Defeated 1000 enemy units.
Obtained all ship parts.
Gave ship orders 15 times.
Defeated 15 enemy aces.
Gave direct commands 15 times.
Completed a squad story for the first time.
One of your classes was promoted to Paragon status.
Kept your promise with Riley Miller.
Completed Chapter 18, and ended Belgar's dark ambitions.
Learned all orders.
Completed Chapter 17, and witnessed the end of the war.
Rescued 10 allies in critical condition.
Completed Chapter 15, and defeated both Walz and Crymaria.
Obtained A ranks on 20 missions.
Completed Chapter 11, and made it past the Sea Fortress.
Gave orders 15 times.
Earned 1,000,000 DCT cumulatively.
Developed the Hafen into a heavy tank.
Completed Chapter 7, and rendezvoused with the Centurion.
Defeated an enemy ace for the first time.
Completed Chapter 4, and won the battle of Siegval.
Completed 10 missions without anyone in critical condition.
One of your classes was promoted to Elite status.
One of your squadmates was promoted to Corporal.
Learned an order at the Mess Hall for the first time.
Used R&D Facility for the first time.
Obtained an A rank on a mission for the first time.