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