Here is the full list of all 31 Yoku's Island Express achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Activate all Scarabs
Hatch the God Egg
Collect all Wickerlings
Try every ball style
Unlock all treasure chests
Complete the story
Become the Postmaster
Collect every ability upgrade
Get the biggest wallet
Defeat Screetch
Complete the temple trials
Complete Willo's quest
Discover the heart cluster at the bottom of the sea
Toot the noisemaker 1000 times
Complete Rinri's quest
Complete Thorn quest
Deliver the cake to the inventors house
Discover Fosfor’s Lair
Unlock all the Beelines
Collect the Divefish
Save Spina
Defeat the Spider
Ride the Beeline
Befriend a Sootling
Customise Yoku’s ball
Take the surviving egg to Dipperloaf
Find the Post-office
Suck up a slug with the Slug Vacuum
Toot the noisemaker 100 times
Free Kickback
Blow the noisemaker