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