Here is the full list of all 34 CHAOS;CHILD achievements.
Mastered Chaos;Child
Made No Mistakes When Putting Up The Data
Got It Wrong On a Mapping Trigger 20 Times
Tried All Delusion Triggers
Saw All Event CG
Saw All TIPS
Saw All Negative Delusions
Listened to All Sound
Reached the Silent Sky End
Reached the Dream Sky End
Discovered the True Route
Saw All Positive Delusions
An Amazing Wind Blew
Discovered Uki Yamazoe’s Chapter
Reached the Deep Sky End
Discovered Hana Kazuki’s Chapter
Reached the Bad End
Reached the Dark Sky End
Discovered Hinae Arimura’s Chapter
Reached the Real Sky End
Discovered Nono Kurusu’s Chapter
Didn’t Get Scared, and Tried a Delusion Trigger
Reached the Over Sky End
Started Chapter 11
Started Chapter 10
Started Chapter 9
Started Chapter 8
Started Chapter 7
Started Chapter 6
Started Chapter 5
Started Chapter 4
Started Chapter 3
Started Chapter 2
Started Chapter 1