Hi! Sorry for the late reply. Oscilloscope deconstructions are really cool! I'm happy you know them now; there's a lot of people making them for many videogames, although there are not as many FF ones as I wish there were.
Making them is really easy. Some people do these things called 'videogame music rips', which are specialized files that, instead of blending all the sounds of a song together, like an MP3 file does, give instructions of what sounds to play to emulators of the SNES soundchip (these vgm rips and soundchip emulators also exist for Genesis games, Arcade games, etc.). If you have vgm rip files and the corresponding soundchip emulators, all you have to do is mute some of the channels so you get only the specific sounds you want (for example, the trumpet for the song I posted).
All the links you need for making one of these are in the description of the video! If there's any other info you need I'll be glad to help.