Wanda Maximoff aka Scarlet Witch made her first appearance in X-Men #4, and upon her debut, it became immediately clear that she was on a whole other level with the amount of power she could wield. Anything or anyone Scarlet Witch pointed at would be cursed with an immediate catastrophe without any hope of avoiding a disaster, and this power was known as her Hex. Initially, Scarlet Witch’s Hex was her only power until readers learned that she was also an incredibly strong magic user on top of her pre-existing Hex ability–though there was one added skill that Scarlet Witch exhibited even before magic was officially added to her arsenal within Marvel Comics continuity.
In Avengers #22 by Stan Lee and Don Heck, the Avengers are legally forced to disband after they are framed for a string of criminal activity across New York City. All of the former members go out looking for work since they can no longer make a living as superheroes. Because none of them really have any skills aside from the ones granted them by their superhuman abilities, Scarlet Witch, Quicksilver, and Hawkeye join a circus. However, their eventual employment comes after numerous rejections by so many other jobs, including the theater where Scarlet Witch tries to break into the live entertainment industry using a skill that no one knew she had until this very moment: the ability to sing.
While technically anyone with a voice has the ability to sing, Scarlet Witch seems to think that she has what it takes to make it as a professional singer in New York City without any prior experience. The confidence one has to have to tell a theater director that they are ready to go out onto the stage and sing so divinely that they are able to consistently earn a livable wage is astronomical. That would seem to indicate that Scarlet Witch actually does have the pipes to back it up.
Unfortunately, as it currently stands in the MCU, Scarlet Witch is presumed dead so fans may never get the chance to hear her seemingly beautiful voice. However, it is unlikely that Wanda is gone forever especially after all of the development her character has undergone just in Phase 4 of the MCU alone, meaning there is still hope that Scarlet Witch will use her greatest power in the MCU and sing a song that is truly worthy of the stage she sought to conquer in the comics.