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