Weissman is a New York City-based model and actress. She started her career as a model at the age of eight, following in the footsteps of her mother whose agency discovered her. She has appeared in major designers and brands like Calvin Klein, Ralph Lauren, Levi's, Benetton, DKNY, H&M, among many others. As an actress, she has appeared in commercials for ACT mouthwash, Maybelline, Purell and My Little Pony.
She made her film debut playing the role of a young April O'Neil in the science fiction action comedy film Teenage Mutant Ninja Turtles, the role played as an adult by Megan Fox, in 2014.
In 2015, Weissman appeared in the CBS and Warner Bros. Television's superhero series Supergirl as a young Kara Zor-El, played as an adult by Melissa Benoist.
In 2016, Weissman appeared in the film Thirsty Girl, and had the significant role of Rebecca Brand in the comedy film Nine Lives, also starring Kevin Spacey and Jennifer Garner, which was released in August, 2016.
|2014||Teenage Mutant'Ninja Turtles||Young April O'Neil|
|2016||Thirsty||Girl in Pink|
|2016||Nine Lives||Rebecca Brand|
|2015-2016||Difficult People||Renee Epstein||2 episodes|
|2015–2016||Supergirl||Young Kara Zor-El||7 episodes|
|2017–present||A Series of Unfortunate Events||Violet Baudelaire||8 episodes; main role|
- Weissman had also worked with Barry Sonnenfeld in Nine Lives.