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