Any resources to help decompile a PSP game?

[SlaycrolTV]

Made an account because i can't find clear answers and would appreciate some pushes in the right direction with this.

I'm a programming scrub but a determined one and i have hopes to decompile/reverse engineer Dissidia 012, inspired by old fighting games slowly getting rollback netcode retrofitted into them and wanting to (if even possible lol) revamp the online structure to fit.

Any resources to inch me in the right direction with this ambitious idea?
I have a little theory knowledge to work with but basically no practical with PSP architectures or resources to learn more about how i should approach it even.

Thanks everyone for any advice