If you're looking for manga similar to Show by Rock!! Shinkoushoku Chinkonka IV-juu Sousei Mokushiroku, you might like these titles.
Green Leaves Entertainment is a tiny production company on the verge of going out of business in Sendai, the biggest city in Japan's northeastern Tohoku region. The agency once managed the careers of magicians, photo idols, fortune-tellers, and other entertainers, but its last remaining client finally quit. In danger of having zero talent (literally), the president Tange hatches an idea of producing an idol group. On the brash president's orders, the dissatisfied manager Matsuda heads out to scout raw talent. Matsuda makes a fateful encounter with a certain girl...
Nanahoshi Ren, a lonely college student who continues to aim for "that person" that he saw live when he was young. One day, when I was singing alone at karaoke, I was scouted by a band - the band activity of 5 people of "Argonavis" who became destined is starting!
Kasumi Toyama has always been captivated by the "beat of the stars". Since then, she’s been searching for something… a spark that’ll excite and thrill her! Following a trail of star-shaped stickers, she soon stumbles upon a Random Star guitar at her school mate’s house! Could this mark the start of something amazing?