A tip on how to swap discs on Retroarch along with building a playlist to make disc-swapping almost seamless and the game saves should work between discs as opposed to the problem I had where the saves disappeared.
I looked up the info online and it wasn't completely clear to me, but I hope this it clear enough for all of you to understand so I wish you all some good luck and have a good time with your future emulations!
Editing File Extensions: https://www.wikihow.com/Change-a-File...
Creating .m3u file: https://forums.libretro.com/t/how-do-...
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