Update on this, I used a flag event injector, credits to @theSLAYER, which allowed me to start off from the exact fight I was on before. I had old screenshots of my team's EV & IV info, so I actually managed to beat the game today lol.
I need some help restoring my old game. I recently lost my data and had to reset my Pokémon USUM save. Something about my 3DS CFW crashed it during the Lusamine fight and I had to revert my 3DS to an older version without my save file. I only need to be at or near the fight where you beat Guzma and then go onto Lusamine, not the first appearance. If anyone knows how to go to a specific area with Event Flag editing or something like that I'd really appreciate some insight.