I have put together a list of theme songs for each player on the itch.io page! If you are not mentioned, please say so, and I will correct it. Also, if you want a different theme, please say so as well.
(These are not meant to be accurate, but what I imagine a player would have)
LIST-
Bowboi - Ganondorf Battle, The Marcus Hedges Trend Orchestra
Aza222 - Romeo & Juliet, Dance Of The Knights
A Little Thing - Le Marseillaise
Sir Dumb The Stupid - Lacrimosa, Wolfgang Amadeus Mozart
Starsket - The Unkillable Soldier, Sabaton
Alphin - Fluffing a Duck, Kevin MacLeod
Platon - One Winged Angel, Nobuo Uematsu
Havoc - The Battle Hymn Of The Republic, USAFBSC
B2DK - Carmina Burana: O Fortuna
Kitss - Song for Denise, Piano Fantasia
Zephyr - You're The Best, Joe "Bean" Esposito
Noob Killer - Clarinet Polka - Jimmy Dorsey
Crusader Mantis - Chirp, C418
Sopfr - At Doom's Gate, Daniel Tidwell
Frostbite - Monke Need to Swing, Stunshine
Chai Cat(Shiny) - Blood On The Risers
Hunter - Derp Song, Derp Bros
Alexitop - William Tell Overture, Gioachino Rossini
Madara Uchicha - Sad Violin Music
Aussua - In The Hall of The Mountain King
Shadow - Voyrin marssi, Mieskuoro
Nina - Duty, Steel My Heart