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