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