Here is the full list of all 9 What Remains of Edith Finch achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Play Calvin's story again
Knock all the letters of Gregory's name into the bathtub
Take both paths to the house
See Johann's name in the ending credits
Finish all stories
Look in all peepholes and telescopes long enough to hear Edith's commentary
Clear all balls off the pool table
Let the drunken sailor finish his song
Catch 2 rabbits with only 2 swoops