Sports anime about things that can only vaguely be considered sports.

Hibike! Euphonium, Initial D, March comes in like a lion are more obvious ones but band anime like K-On!, Bocchi the Rock!, and Nana also have a similar appeal.
These all have some kind of competition or performance involved, so they are structurally similar to sports anime with character drama and training/practice leading up to a big climax that caps off both the drama and the training.

Maybe this genre isn’t so niche as these shows are all very popular, but I don’t often see people consider them to be similar in any way.