Lucky Star and K-on for CGDCT
Evangelion for meta-commentary and deconstruction, to the point that future works that qualify often get called the “Evangelion of <genre>”
Fullmetal Alchemist Brotherhood and Attack on Titan for battle shounen
Bocchi the Rock for girls band anime, specifically
Lupin III: The Castle of Cagliostro for pretty much all of Ghibli
Akira for 90s anime
Nope, I was in my 20s back then. this is older. the same period as first ranma 1/2 anime. around that. and yes, as I was watching PMMM weekly back then, That Episode blew my head.
No idea then, sorry.
Google suggests Magic Knight Rayearth or Phantom Thief Jeanne, neither of which I’m familiar with, but they don’t look like they fit.
Saint Seiya could fit the dates, Athena could pass as a chosen one, and Cygnus had a buckler of sorts, but that’s probably not it either…