Lee released an unofficial solo song "Dream Words" (夢言) on 1 June 2021 on his own YouTube channel.

[7] His fans, named unicorns, spent thousands of HK dollars to promote the song at various bus stops.

[8] They also organised an advertisement campaign, and art exhibition at the Jao Tsung-I Academy, purchasing various billboards at prime locations and decorating public buses with Lee's pictures for his twenty-sixth birthday.

On 5 May 2023, along with Jer Lau of Mirror, Lee performed a duet version of Lau's solo song "Stellar Moments of Humankind" on the popular Youtube channel "The First Take"[12] The duo becomes the second and third artist of Hong Kong to be featured on the channel.

On 30 August 2023, Lee held his debut solo concert MOOV LIVE Jeremy at the Hong Kong Convention and Exhibition Centre.