Debut (2018)

A popular teenager inexplicably finds herself in the body of an unpopular classmate -- and her body's new owner has no intention of switching back.

The series centers on Ayumi Kohinata, a first-year high school student who has a cute and shy personality. She's excited that she just started dating her first boyfriend, but on the day of their first date, she gets a mysterious call from her classmate Zenko Umine. Zenko says she's going to die, and Ayumi witnesses Zenko jumping from a building. The next thing she knows, Ayumi wakes up in a hospital, but in Zenko's body.

Both dramas include the hash and the sweet of the life of idol trainees and the chemistry between the group members. Debut contains an extra element of fantasy but in the core it's an idol drama.

Both dramas involve around an idol boy group and also have an element of who-is-who confusion going on... just in quite a different way.

Similar theme of having two bodies for one soul. When the other slept the other awake. Both tackle the problem of appearance. But Debut focused more on dreams as a star. Lookism is more than that and a bit more complex.
You'll have some relief watching Debut. As it's about idol, they have some great OSTs too.