As for singing, Guo says that she didn't take it seriously and only sang for fun at choirs during her childhood. Her talent for singing was recognized by her music teachers. When she studied in the Juilliard School's Pre-College program, Guo was trained with a double major in piano and classical voice. Since then, she has been developing a career both as a pianist and a soprano.

She recently graduated from the Juilliard School with a Bachelor of Music in piano.

"A very fine pianist with a beguiling voice. Here is a rare talent," said BBC Music Magazine upon the 2021 release of Guo's debut recording Chopin: In My Voice, featuring interpretations of a range of Chopin's piano compositions augmented by performances of several of the composer's art songs, plus an aria by Italian composer Gioachino Rossini in which Guo accompanies herself.

"Chopin's music is always close to my heart. In the album's name, the 'voice' means both the voice of the piano and my own," says Guo. She made the album when she was preparing for the National Chopin Piano Competition in the United States in 2020, at which Guo won a top prize.