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
Get the biggest wallet
Hatch the God Egg
Collect all Wickerlings
Complete Thorn quest
Unlock all treasure chests
Collect every ability upgrade
Complete Rinri's quest
Complete Willo's quest
Try every ball style
Become the Postmaster
Deliver the cake to the inventors house
Take the surviving egg to Dipperloaf
Complete the story
Defeat Screetch
Discover the heart cluster at the bottom of the sea
Complete the temple trials
Unlock all the Beelines
Discover Fosfor’s Lair
Defeat the Spider
Befriend a Sootling
Toot the noisemaker 1000 times
Customise Yoku’s ball
Save Spina
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