Here is the full list of all 27 Ooblets achievements worth 1,000 gamerscore. It takes around 20-25 hours to unlock all of the achievements on Xbox One.
Sell 100 crafted items
Sell 50 crafted items
Scan 25 ooblets at the Lernery
Travel to Tippytop
Collect 40 things from the sea dangler
Travel to Pantsabear Hill
Win 3 dance barn tournaments
Complete 20 Tinstle Tasks
Craft 20 items
Collect forageables from 4 different regions
Travel to Port Forward
Fulfill 15 Plenny's orders
Travel to Nullwhere
Get 10 friendship stickers
Scan 10 ooblets at the Lernery
Travel to Mamoonia
Get 3 friendship stickers
Complete 10 Tinstle Tasks
Harvest 50 crops
Look at 10 thingiedoodles
Get 150 friendship points
Scan 3 ooblets at the Lernery
Complete 5 Tinstle Tasks
Win 15 dance battles
Plant 15 seeds
Win 5 dance battles
Collect 60 forageables