Issa was born and raised in Montreal, Quebec, growing up as an Anglophone on Montreal's West Island.[6] She had a troubled childhood, and at one point lived in a group home.[6] When she was 15, she was a client with the Batshaw Youth and Family Centres, a local nonprofit assisting troubled youth.[6] As a teenager, she suffered from depression, anxiety, and eating disorders,[6] but despite this, she began working toward a modeling career, which proved to be unsuccessful, something she attributed to her athletic build.[7] In her twenties, she worked as the assistant front-desk manager at a Montreal hotel before being fired.[6] Looking for a new career, she shifted her focus toward athletics, and after a brief time in kickboxing, began to practice Brazilian jiu-jitsu.[7] By 2010, she had won the heavyweight adult female white belt (novice) category at the International Brazilian Jiu-Jitsu Federation World Championships.[1] Around this time, she landed a breakthrough role in a major picture, Immortals (2011), through old modeling connections.[7][3]
Her role in Immortals was followed immediately with a role in The Bait (L'Appât), a French-language buddy copaction comedy film where she plays a "kind of Ninja assassin" who pursues the main characters.[6] Her television debut, in 2011, was a small role on the French-language series 30 vies. This was followed by a number of minor roles in English-language films like Warm Bodies and Betty and Coretta (both 2013), as well as Brick Mansions (2014), which was Paul Walker's penultimate film. In 2014 she landed a major role in the French-language television series Unité 9 (fr), broadcast on Ici Radio-Canada Télé. Sometimes compared to Orange Is the New Black,[8] the series is also set in a women's prison. Issa played Bouba, a "mean piece of work who makes life a living hell for the other female prisoners."[6] This role raised her profile considerably in Montréal and Québec.[6]
She won again at the 2014 International Brazilian Jiu-Jitsu Federation World Championships, this time competing as a heavyweight blue belt. She subsequently decided to withdraw from competition to focus on her acting career.[3]