The character is a reboot version of Shuriken (Kyoko Shidara) from Victory comics, with similar aesthetic and powers. It isn’t known if both characters are related or are the same.
Brittany Chien is a top agent for Aladdin, with ultra improvements,who is working for them because her ill child is affected with Ultra powers and is in Aladdin custody. She only answer to G.E.N.I.E. itself. She was ordered to kill Rune and capture Gemini. For various reasons, she failed in this mission and was encapsulated.
After she was ordered to capture Amber Hunt, Shuriken finally rebels against Aladdin and crossed into the All New Exiles, forming part of the team of mutants and ultras.
Her backstory is unknown, only knowing that she worked for the Japanese mafia called “Techuza”