If you're looking for manga similar to Dear Boys Act 2, you might like these titles.
Tired of constantly being compared to his prodigious older sibling, Riku, Raimu decides to take him head-on by surpassing him in the field of basketball.
The very tall Ryudo Kagetora aims to be the best basketball player in Japan! He has chosen a formerly famous basketball high school, in order to bring it to new glory. He also dislikes girls, ever since a girl beat him at basketball in grade school. There is also another new ace player joining the basketball team, Ichinomiya Chiaki. However, Chiaki was an ace on the middle school women's basketball team. She becomes a man when she's on the basketball court, and she was kicked out of women's basketball team when her quirk is revealed. Ryudo learns her secret, and reluctantly becomes her ally and roommate!
The story about Mishima Dunk, a small boy who dream to be the first Japanese NBA player.
Satou Yuuho gets called out by the cute basketball club manager, Koganei Mao. He thinks that it is a love confession, only to find out that it is only to help the basketball club.
The manga is set one year after Kazuhiko and Mizuho High School's inter-high victory, and is set in the famous Shōnan Dai Sagami High School, Mizuho's rival school. The manga centers on Fuse, the school basketball team's ace who aims for the nationals, and a new freshman protagonist.