Wich genre would you say that the International Super Star Soccer 64's main theme is?
Also, what about the training theme?
It's videogame music. Specifically, it is videogame music for the N64, from Japan. The music isn't part of any other genre as its sole purpose is to amuse and therefore takes several elements at whim. The core of the music, the trope of music that grounds it is found in prior Mario music composed by Koji Kondo, Seiichi Tokunaga, and Kenta Nagata.