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