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
Try every ball style
Get the biggest wallet
Collect every ability upgrade
Hatch the God Egg
Collect all Wickerlings
Complete Rinri's quest
Unlock all treasure chests
Complete Willo's quest
Become the Postmaster
Discover Fosfor’s Lair
Complete Thorn quest
Complete the story
Defeat the Spider
Toot the noisemaker 1000 times
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
Collect the Divefish
Ride the Beeline
Save Spina
Take the surviving egg to Dipperloaf
Find the Post-office
Toot the noisemaker 100 times
Suck up a slug with the Slug Vacuum
Free Kickback
Blow the noisemaker