Chara Zenkai T2!

Name: Chara
Key: Kazuki Alter
Skill or Tier S: Saiyan Zenkai T2

Reasoning: Chara had awakened a new power in herself that was related to her race. She didn't quite know what it was but judging from her fellow saiyan's reactions, she was the first to acquire it. During that sin fight, she used it to her full potential, however, failling in the process and being defeated. The power was lost and never to return but she felt something else grow in her from it.

TL;DR: Despite losing FSSJ in the fight against the sin, she should've gained something from having it then after being defeated.