Here is the full list of all 20 Rogue Company Playtest achievements.
Play 25 hours in a party
Complete the tutorial
Fully upgrade a primary weapon
Win 100 matches
Pick up another player's weapon and down an enemy with it
Revive a total of 100 players
Win 8 matches with 8 different Rogues
Win a match without purchasing a primary weapon
Down an enemy while riding a zipline
Deal 1,000 damage with gadgets
Deal a total of 10,000 damage to players via headshots
Purchase 3 perks in a single match
Accrue a total of $70,000 in a single match
Down 20 enemies in a single match
Down 10 enemies
Down 4 enemies in one round
Down an enemy with a melee weapon
Down an enemy without taking return damage
Down an enemy with a gadget while looking away from them
Down an enemy while you have less than 10% health