Chavez was created by Joe Casey and Nick Dragotta for Vengeance #1 in 2011 but her backstory and abilities were only explored in 2013 in Kieron Gillen and Jamie McKelvie's Young Avengers.
MCU entry
Chavez's first MCU appearance was alongside Benedict Cumberbatch's Stephen Strange inĀ Doctor Strange in the Multiverse of Madness who put everything at stake to help her.
Backstory
Chavez is from Utopian Parallel where she was raised by mothers who were co-rulers of this dimension. When mysterious forces attacked their universe, Chavez's mothers sacrificed themselves.
Development
After the death of her mothers, Chavez fled from her home. In Doctor Strange 2, Xochitl Gomez essayed the role of Chavez who traveled across universes by conjuring star-shaped portals.
Powers
Contrary to the film, Chavez can control her powers quite well. She has superhuman strength, durability, speed, and the ability to fly. Her star-shaped portals break barriers between dimensions.