Here is the full list of all 27 Ooblets achievements.
Travel to Tippy Top
Travel to Pantsabear Hill
Scan 25 ooblets at the Lernery
Sell 100 crafted items
Sell 50 crafted items
Fulfill 15 Plenny's orders
Craft 20 items
Win 3 dance barn tournaments
Collect forageables from 4 different regions
Collect 40 things from the sea dangler
Complete 20 Tinstle Tasks
Scan 10 ooblets at the Lernery
Travel to Port Forward
Travel to Nullwhere
Get 10 friendship stickers
Complete 10 Tinstle Tasks
Harvest 50 crops
Get 3 friendship stickers
Win 15 dance battles
Travel to Mamoonia
Plant 15 seeds
Get 150 friendship points
Complete 5 Tinstle Tasks
Scan 3 ooblets at the Lernery
Look at 10 thingiedoodles
Win 5 dance battles
Collect 60 forageables