Many of the pokemon games have been dissasembly, if you only wanna change sprites and names thats the way to doit, all those include a repack file. It requieres low hacking skills, probably install and run some cmd commands, if you wanna make something more difficult as change moves, create new items, change video secuences etc... that will requiere to learn asm,coding and study the console cpu.
I would like to make a small team to help out with this passion project.
Try to sell your project, your sentence sounds like you wanna people to do stuff for you.
If you have something done, show it up will be a good idea too.