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