Here is the full list of all 40 XCOM: Chimera Squad achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Win the campaign on Impossible difficulty.
Complete all versions of each Faction’s Takedown mission over multiple campaigns.
Buy 20 unique Scavenger Market items in a single campaign.
Relocate the same unit with Shelter and his ghost in one turn.
Complete a mission with only one Agent left standing.
Hack an enemy Android with Patchwork and trigger Self-Destruct.
Use Claymore to detonate a Shrapnel Bomb with another explosive.
Move a VIP with Shelter’s Relocate and Torque’s Tongue Pull.
Complete a mission without killing a single enemy.
Complete an encounter by only dealing damage with melee attacks.
Clear an entire encounter during the Breach turn.
Use every Agent in at least one mission.
Win the campaign.
Complete the Gray Phoenix Investigation.
Replace an Agent mid-mission with an Android.
Complete every Spec Op at least once in a single campaign.
Fully upgrade an Android.
Reach max rank with all Agents in a single campaign.
Have Rank 3 Field Teams in all nine districts.
Use Verge to do 10 or more damage with one Mindflay.
Complete 20 Assembly Projects in a single campaign.
Use every type of Breach point.
Capture a Praetorian.
Use Blueblood to hit 3 or more enemies with one Phase Lance shot.
Complete the Sacred Coil Investigation.
As Godmother, activate Overtime and down an enemy on both turns.
Complete all of one Agent’s class training.
Capture a Ronin.
Launch a mission with no human agents in the squad.
Unlock all Field Abilities.
Have 8 Agents in the squad in a single campaign.
Kill an enemy with Axiom while Berserk.
Equip an Epic Weapon.
Have Kinetic Armor on all 4 squad members at once.
Use Torque to Tongue Pull an enemy into poison.
Complete the Progeny Investigation.
Use Zephyr to hit 3 or more enemies with one use of Crowd Control.
Complete an objective with an action from Terminal’s Cooperation.
Capture a Sorcerer.
Complete the tutorial.