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