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