Here is the full list of all 39 Spiritfarer achievements. It takes around 35-40 hours to unlock all of the achievements on Windows.
Accomplish your very last objective
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Bring all releasable spirits to the Everdoor
Make all spirits reach the ecstatic mood at least once
Collect all figureheads
Give a dating advice
Complete all collections
Activate all the shrines
Fully improve Elena's Cubicle
Shear sheeps at least 50 times
Discover all recipes
Sign up to Feedorama
Find and shelter all sheeps
Sell at least 200 items
Light up all Lighthouses
Have your final conversation with Hades
Fully improve Buck's Lair of Wonders
Build all houses and stations at least once on the boat
Fully improve Gustav's Gallery
Use Alex's bus stops 50 times
Complete thirty errands for Francis
Have your second conversation with Hades
Fully improve Atul's Workshop
Fully improve Stanley's Playroom
Fully improve Bruce and Mickey's Crib
Fully improve Astrid's Bungalow
Endure 10 of Albert's jokes
Do not tell Astrid about Giovanni's night excursions
Tell Astrid about Giovanni's night excursions
Buy at least 100 items from Raccoon Inc
Fully improve Alice's Cottage
Make 5 spirits reach the ecstatic mood at least once
Fully improve Summer's Sanctuary
Complete twelve errands for Francis
Have your first conversation with Hades
Fully improve Gwen's Lodge
Give Furogawa Tour's guide a tip
Complete one errand for Francis
Make one spirit reach the ecstatic mood at least once