Mecia started her career as a model after winning Britain's Next Top Model in 2009. She then relocated to London where she enjoyed a successful career internationally. Later, she put modelling on pause to train as an actress at Italia Conti Academy of Theatre Arts, where she graduated in 2019. 

Shortly after graduating she secured a role as a supporting series regular playing the Elven Queen Francesca Findabair in Netflix series The Witcher: Season 2. She continued to film season 3 which was released on June 28th 2023.

Her filming for The Witcher: Season 4 is scheduled to start early 2024. Additionally, Mecia will star as the lead character Agnetha in the film Bjorn of the Dead. This project has garnered significant endorsement from heavy metal band Iron Maiden, with filming slated for February 2024.