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