Here is the full list of all 91 My Time At Portia achievements. It takes around 200 hours to unlock all of the achievements on Windows.
You were at fault...
Accept the proposal from Mint.
Accumulatively give out 500 gifts.
Throw ten parties.
Complete Phyllis's Dream
Complete the adventure in the cave with Arlo.
Accept Gust's proposal.
Enjoy some fireworks with Dr. Xu.
Defeat 30 rare monsters.
Propose to Emily in front of the Pumpkin Princess House.
Complete all five Dee-dee transport commissions.
Unlock all backpack slots.
Win 20 games of Rock Paper Scissors in 3-0 fashion.
Expand the land area of the workshop to the maximum.
Accumulated 10 meals during dates and play dates.
Successfully make 30 different dishes.
Cumulatively picked up 500 feces.
Get 300 items by kicking trees.
Getting divorced.
Place first in five fishing competitions.
Win the highest possible award in the Slots mini-game.
Win at Cross Five 50 times.
Achieve the relationship "Happy Child" with your kid.
Accumulatively give out 50 gifts that people like.
You missed a date.
Try lasso roping for 50 times.
Complete 150 Commerce Guild commissions.
Fail at cooking 1 time.
Have or adopt a second child.
Clear Level 100 of the Deepest Ruins.
Recognize 5 different constellations.
Have or adopt a child.
Find more than 10 Ghost Badges in a single Day of Memories event.
Have maximum Stamina reach 600.
Accumulated 10 times during the Doodles mini-game where the play date is happy with the result.
Complete the main storyline.
Used all items from the Vending Machine in the Deepest Ruins.
Get to Level 50 of the Deepest Ruins without using Vending Machines.
Clear Level 50 of the Deepest Ruins.
Provide 100 Data Discs to the Church of the Light.
Meet Pa.
Have maximum HP reach 2000.
Achieve the best relationship with your spouse.
Clear Level 10 of the Deepest Ruins.
Accumulated 10 times in the Swing mini-game where the play date is happy with the result.
Enter the Deepest Ruins.
Give out a gift that the other person doesn't like.
Defeat the rogue knight and All Source.
Getting caught by the Sky Shark Pirates.
Recover 15 different types of relics.
Be ranked number one in a seasonal workshop ranking.
Throw a party.
Everyone likes you!
Completed 100 Inspections at the Commerce Guild.
Adopt Scraps.
Play the seesaw and get your playmate to catch a bird.
Finish with a over 90% accuracy rate in the Balloons mini-game.
Use 50 Fireworks in one setting.
Workshop reputation reaches Level S.
Defeated all the people that can spar in Portia.
Congratulations!
Pass the trials set by Ginger's family.
Encounter the rogue knight.
Place 5 advertisements in the Portia Times for the workshop.
Gather 50 assembly diagrams.
Complete the new Portia Harbor.
Did I just use the Blender to mix feces...?
Complete South Block.
Talk with other town folks over 500 times.
Get more than 40 Ghost Badges in Haunted Cave Exploration.
Find a diamond.
Keep the spiciness of the hotpot above 85 for 10 seconds during the Winter Solstice festival.
Help build the Portia Bridge.
Clear all the levels in any Hazardous Ruins.
Adopt Pinky.
Open 50 treasure chests.
Opening Of The Museum
Help fix Ack the living AI.
Pass the test to enter the Collapsed Wasteland.
Gain 150 points in the Dart game.
Provide 100 Data Discs to the Research Center.
Help the Portia Tree Farm be operational again.
Forced to sleep at 3:00 in the morning.
Cut down 200 trees.
Accumulate 10,000 Gols.
The first photo taken with someone else.
Pick up 7 gifts during the Day of the Bright Sun event.
Discover a mysterious room in Abandoned Ruins.
Enter the Abandoned Ruins for the first time.
Register your workshop.
Arrive at Portia.