I made a mass-renamer that worked for my setup. I can't make another new thread until tomorrow because this is a brand new account but I'll upload it to this post. It's a windows program.
The program can mass rename isos to game.iso. So you can select a folder, and the program will look into every folder in that, and if those folders have isos in them it will rename them to game.iso
There's a second function that compares folder names, and if 2 folder have the same name except for having a 1 and a 2 being the only difference in their name, i.e. "this game (Disc 1)" and "this game (Disc 2)" it will rename the iso in the 2nd folder to "disc2.iso", move the iso into the first folder, delete the second folder, and if the folder contains the text "(Disc 1)" it will also remove that from the folder's name.
I made it in visual studio, which has problems with display sizing. I made it on my 4k tv so if the display needs adjusted please let me know. Eventually I should be making a thread for this program where I can get feedback about it.
And I am posting it in this thread because this was the thread that prompted me to make the program; this thread shows up on google easily so I am posting it here because a program that does this exists now and should be mentioned in a thread that says one doesn't.
It's called Wiinamer.