Wow-- this is so cool. Maybe someone can fix that MissingNo glitch I kept running into as a kid? ;)
PureRGB [1] is a very comprehensive hack that fixes a bunch of bugs from the original game and adds a bunch of new content. All of the elementary school playground rumors are implemented as well like Bill's backyard, Mew being under the S.S. Anne truck, etc. I played through it last year until just before Victory Road before getting sidetracked by more important life events. I'll probably pick it back up sometime later in 2025.
The Shin Pokemon and Pure RGB hacks both have various fixes relating to missingno. Both are based on this decompilation.
I've only played through Shin Pokemon and enjoyed the nostalgia.
https://github.com/Vortyne/pureRGB https://github.com/jojobear13/shinpokered