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