I produce electronic music and am dying to collaborate with someone for some inspiration and new experiences! Metroidvanias are my favorite and there's no better genre to inspire me to make something epic and awesome for your game
Although I don't have jam experience, I've been told I have chops - see below for a sample of background music I made for a friend's turn-based cyberpunk JRPG. Maybe this style is something you would love to have as well:
https://soundcloud.com/aronahlam/sets/music-for-an-unrealized-video
You'll get a wide variety of melodic beat-oriented tunes (or ambiance) with techy sounds and live instrumentation samples - tempos range from trip hop to ambient, house, downtempo, synthwave, trance, etc. Need epic crescendos for your story's heartbreaking finale? Or creepy sinister ambiance for navigating the main villain's lair? Or peaceful tunes for a hub area to chill your player out? Or a badass heart-pumping stomper for getting the player in the mood to murder hundreds of enemies in a limited amount of time?
Hope to work with you and have some fun :)