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