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