Here is the full list of all 26 Warhammer: Vermintide 2 achievements. It takes around 120-150 hours to unlock all of the achievements on Windows.
Complete a level as every Hero
Complete Skittergate on Recruit
Equip an Exotic Item
Salvage 100 items
Complete Act 2
Complete Act 3
Equip a Rare Item
Craft an Item
Complete Act 1
Unlock 1st Talent point
Equip a Common Item
Salvage an item
Complete Prologue
Complete Skittergate on Veteran
Complete Skittergate on Champion
Complete Skittergate on Legend
Reach level 30 with Kerillian
Reach level 30 with Saltzpyre
Reach level 30 with Kruber
Reach level 30 with Sienna
Reach level 30 with Bardin
Reach Level 30 with all characters
Unlock all Talent points for 1 career
Craft 50 items
Equip Exotic items in every slot
Equip a Veteran Item