Her name is Jinsil and she recently re-debuted for the fifth time in Blastar.
She officially debuted in 2015 when she was added to the group G.I (Global Icon) with the stage name Heeso.
Later that year she debuted in the group HEXE under the stage name Jin
In 2016 she was added to the new lineup of AGirls (using the Heeso stage name again)
Then in the beginning of 2018 she was added to the new lineup of Various
Just a couple weeks ago she has debuted with rookie group Blastar and is promoting with the stage name Jinsil
Another interesting fact: she's also a background dancer for Black Pink (she's the one standing on the far right
She was also a background dancer for AOA's Chanmi (right)
Background dancer for Lee Hi (standing next to Lee Hi)
Finally she was in Solo (standing far right)