[2] In 2019, Eunsang competed on the show Produce X 101 representing Brand New Music alongside Kim Si-hun, Yun Jung-hwan, and Hong Seong-jun, now of BDC.

[4] On August 31, 2020, Eunsang made his solo debut with the single album Beautiful Scar.

[5][6] In October, Eunsang collaborated with former X1 groupmate Kim Woo-seok for the single "Memories".

[8] On February 14, 2022, it was announced that Eunsang will be part of Brand New Music's upcoming boy group Younite.

[9] On April 20, 2022, he debuted as a member of Younite with the release of their first extended play Youni-Birth.