Here is the full list of all 21 Misao: Definitive Edition achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Give Misao some coins
Clear Truth with the male protagonist.
Clear the main game with the male protagonist.
Find the message in the back of the laboratory.
Free Kurata in the Truth route.
See the bad ending.
Clear Truth with the female protagonist.
Clear the main game with the female protagonist
Play the piano.
Talk with Library multiple times.
Hide in a cardboard box.
Save Kudoh.
Refuse to help Yoshino.
Jump off the rooftop.
Encounter Hanako.
Check your key items.
Get a whiff of a toilet.
Have a meal.
Read "The Lazy-Eyed Ranger."
Read the diary in the library.
Make a quicksave.