Early work Alexander worked as a storyboard revisionist for 28 episodes of
The Powerpuff Girls reboot series, which aired on 2016 from to 2019. This job was how she began working in the
animation industry, as a freelancer. Following this, she worked as a storyboard artist for
Stretch Armstrong and the Flex Fighters (2017–2018), a
Netflix series. She specifically emphasized specific colors in the show, with pink and turquoise representing historical symbolism in Mesoamerica Mexico. She began developing the story and its cast of characters in 2007, then developed a pitch for the series in 2011, but took her years of pitching it to companies such as
Frederator,
Netflix, and
Crunchyroll, before it was picked up. Marisa Balkus of Crunchyroll, the Executive Producer in charge of original development of the streaming service, approved the show, after Alexander pitched it in early 2018, arguing that Mesoamerican Mexican culture isn't often portrayed on television and would be interesting to portray in an anime story medium. The series premiered on
Crunchyroll in October 2020. Alexander served as the creator, illustrator, and executive producer of
Onyx Equinox. She also voiced the character K'i'ik, the weapon which "grows stronger once it tastes blood." Alexander described the series having a
touch of anime combined with "truly Mesoamerican characters" and stated that the show was the result of researching ancient civilizations in
Mesoamerica. She also said the series allowed to see the beauty in her own culture and heritage and said that she had the chance to be mentored by Japanese animator Kuni Tomita who also served as supervising director, with Tomita guiding her in being the head of the show. She characterized Tomita as an "animation mom" and an "empowering and incredible force" while noting that Tomita warned her against animating detailed designs of gods, saying animators will hate her for making them do it, and she justified it by saying it is important culturally. was a show writer, and a storyboarder for the episode "The Bet." Alexander, in a November 2020 interview with
CBR, shared her challenge with pitching the series and wanting to do it with "dignity and respect towards Mexico and Indigenous Mexicans" and said that Crunchyroll had been "wonderful to the project." She called the series a translation between her experiences "into the writer's room and into animation." She also called the series a "Mexican project," said she found many of the cast and crew from her personal collections and social media, but said that the show is not an anime, from her perspective, and called Crunchyroll a "great platform" to tell the show's story. However, in August 2020, Alexander had said that creators of animation do not have a say in the marketing of their shows. In other interviews, Alexander described the show as "a love letter to Mexico and to other Mexicans," argued that blood is a main part of the story but not something to fear, said that the show tries to introduce people to Mesoamerican myths. Alexander also said that she hoped that fans of Western animation would "see the appeal of action-drama animation for adults" and stated that the series had help from an
archaeologist/
anthropologist and extensive research to ensure certain aspects of the show's world are inspired by actual history. In December 2020, Alexander was nominated at
Animation Magazine's 2020 Hall of Fame Awards and won The New Voice of the Year Award for her work on
Onyx Equinox. In January 2021, Alexander floated the possibility of a second season of
Onyx Equinox. In early November 2023, Alexander announced that the series had been cancelled, due to "various reasons" beyond her control, thanked fans, said she would share details on the story she had planned for season 2, and asked people to keep supporting Mexican creators. Prior to this, Alexander said that she wouldn't have "been able to represent LGBT+ characters or a story about trauma and grief anywhere else" and was grateful to Crunchyroll despite the budget being "near 1/3 of a lot of western shows" and added that they unionized because she "threatened to leave before production started."
Other work Alexander worked as a storyboarder on another animated series,
Infinity Train, which aired 2019 to 2020. while saying her experience storyboarding on the show helped her with boarding for
Onyx Equinox. In October 2020, Alexander signed a petition calling for better
Latinx representation in
Hollywood. In March 2021, she appeared at a virtual event for
South by Southwest on "animating resilience." She described the animation progress as like "Christmas every day" with new aspects every day, and said that the editing process can be like a "game of telephone." In June 2021, she appeared on a panel at the
Annecy International Animation Film Festival on the influence of anime on creators, with Alexis Hunot, the directors of
Wolfwalkers (
Tomm Moore) and
The Red Turtle (
Michael Dudok de Wit), executive producer of
We Bare Bears (
Manny Hernandez) and a live-action directing team (
Hélène Cattet and
Bruno Forzani). At the panel, Alexander talked about how the anime shows she watched when she was younger influenced
Onyx Equinox. In September 2021, Alexander announced that she'll be working with
Marvel Studios on an unspecified project, with some speculating it may be the second season of
What If...?. She also was a storyboarder for several episodes of the
Crunchyroll series,
High Guardian Spice which premiered in October 2021. In November 2021, Alexander appeared at a panel discussion about Indigenous women in animation at LA Skins Fest. In September 2023, Alexander announced that she joined the staff for the revival of
Phineas And Ferb at
Disney Television Animation as Assistant Director and Storyboard Artist. In March 2024, Alexander mentioned that she was developing a new project at Disney TVA. ==Personal life==