Here is the full list of all 54 Phasmophobia achievements.
Successfully identify The Twins for the first time
Create a custom difficulty
Spend $1
Successfully identify The Mimic for the first time
Reach Prestige I
Reach Prestige III
Successfully identify your first Banshee and survive
Successfully identify your first Demon and survive
Successfully identify your first Deogen and survive
Successfully identify your first Goryo and survive
Successfully identify your first Hantu and survive
Successfully identify your first Jinn and survive
Successfully identify your first Mare and survive
Successfully identify your first Moroi and survive
Successfully identify your first Myling and survive
Successfully identify your first Obake and survive
Successfully identify your first Oni and survive
Successfully identify your first Onryo and survive
Successfully identify your first Phantom and survive
Successfully identify your first Poltergeist and survive
Successfully identify your first Raiju and survive
Successfully identify your first Revenant and survive
Successfully identify your first Shade and survive
Successfully identify your first Spirit and survive
Successfully identify your first Thaye and survive
Successfully identify your first Wraith and survive
Successfully identify your first Yokai and survive
Successfully identify your first Yurei and survive
Reach Prestige II
Complete 100 contracts
Complete 50 contracts
Complete 10 contracts
Spend $10,000
Spend $50,000
Spend $100,000
Complete Training
Complete 50 optional objectives
Obtain the Bronze Apocalypse Trophy
Obtain the Silver Apocalypse Trophy
Obtain the Gold Apocalypse Trophy
Unlock all tier one equipment
Unlock all tier two equipment
Unlock all tier three equipment
Complete 30 daily tasks
Complete 10 weekly tasks
Complete a weekly challenge mode
Complete the weekly challenge mode 5 times
Complete the weekly challenge mode 10 times