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.
Reach level 30 with Sienna
Complete Skittergate on Legend
Unlock all Talent points for 1 career
Reach level 30 with Saltzpyre
Complete Skittergate on Champion
Craft 50 items
Complete Skittergate on Recruit
Complete Skittergate on Veteran
Complete Act 3
Salvage 100 items
Complete Act 2
Complete Prologue
Complete Act 1
Equip an Exotic Item
Craft an Item
Equip a Rare Item
Salvage an item
Equip a Common Item
Unlock 1st Talent point
Reach level 30 with Kerillian
Reach level 30 with Kruber
Reach level 30 with Bardin
Reach Level 30 with all characters
Equip Exotic items in every slot
Equip a Veteran Item
Complete a level as every Hero