Correct abbreviations
RG, RB, RGB, RGBP, RBY
GS, GSC
RS, FRLG, RSE
DP, DPPt, HGSS
BW, B2W2
XY, ORAS
SM, USUM, LGPE
SS
Unpaired third versions use their full name when speaking about them alone rather than with their paired games. I would say Crystal, Emerald, or Platinum instead of C, E, or Pt by themselves. This also applies to when you refer to a single game out of a pair. You would say FireRed over FR or SoulSilver over SS.
Yellow is called Pikachu in Japan, so it would be abbreviated as RGBP if referring to all the main Gen I games in Japan, but this is pointless and it's easier to just say Gen I at that point.
If you see an abbreviation like ORAS or USUM, you shouldn't read it out loud as "Oh-ras" or "Ooh-sum". Abbreviations are meant to make text more concise, not spoken language, and it always sounds stupid and inconsistent when spoken out loud, like spelling out HGSS but reading ORAS as if it were a word.
