Taniguchi was called in to do this whole scene, which is full of references to real players and baseball shows. Probably asked by Mizushima himself since they've worked together.

Looks like Miyamori was emulating Hideo Nomo: https://www.youtube.com/watch?v=T_4JC3t1Hmo

Iguchi looks like Daisuke Matsuzaka: https://www.youtube.com/watch?v=YONcTjKEnN8

Ema's form looks kind of specific, but I can't think of a vertical leg kick outside of Korean Gymnasts giving a first pitch.

As for goth loli, there aren't too many submarine pitchers, let alone lefty submariners, but I can't think of anyone specific (everything before she jumps).