Here is the full list of all 26 STEINS;GATE ELITE achievements.
Played through everything in STEINS;GATE ELITE
Prologue Clear
Chapter 1 Clear
Chapter 2 Clear
Chapter 3 Clear
Chapter 4 Clear
Chapter 5 Clear
Chapter 6 Clear
Chapter 7 Clear
Chapter 8 Clear
Chapter 9 Clear
Chapter 10 Clear
Reached Steins Gate.
Made friends with Kurisu via email.
Reached Kurisu's ending.
Reached Mayuri's ending.
Reached Suzuha's ending.
Reached Luka's ending.
Reached Faris's ending.
Completed all endings.
Saw all TIPS.
Asked by Kurisu to buy cup noodles twice in a row.
Learned why Mayuri started making costumes.
Received an unusual proposition from Suzuha.
Learned about Luka's relationship to his sister.
Offered tea by Faris.