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
Complete Thorn quest
Collect all Wickerlings
Unlock all treasure chests
Get the biggest wallet
Become the Postmaster
Collect every ability upgrade
Try every ball style
Complete Rinri's quest
Complete Willo's quest
Discover Fosfor’s Lair
Complete the story
Defeat the Spider
Unlock all the Beelines
Befriend a Sootling
Defeat Screetch
Toot the noisemaker 1000 times
Deliver the cake to the inventors house
Save Spina
Customise Yoku’s ball
Take the surviving egg to Dipperloaf
Complete the temple trials
Discover the heart cluster at the bottom of the sea
Collect the Divefish
Ride the Beeline
Suck up a slug with the Slug Vacuum
Find the Post-office
Free Kickback
Toot the noisemaker 100 times
Blow the noisemaker