>RBY
>GSC
>RSE
>BW
>XY
The original format: uses the first letter of each game, never required repeating a letter within a generation.
>FRLG
>HGSS
>B2W2
>ORAS
>USUM
2nd format: two words per game = two letters, all caps, and each game still uniquely identified.
>DPPt
The awkward 3rd format: added a lowercase letter to differentiate two games after starting out using only the original format. The t was tacked on the end as a stopgap measure because no one wanted to use the same abbreviation for two games within the generation, and it stuck for lack of a better solution.
So where does that leave us for Sword and Shield?
>SS
No two games within the same generation have ever shared an abbreviation. I personally prefer this, but it still does not fit any established format.
>SSh
Only resembles the 3rd format, but since they're both released at the same time S hasn't been established as the abbreviation for one or the other yet like P was for Pearl. SwS is just as invalid.
>S/S, S&S, SnS, SaS
These are essentially reddit compromises because they're uncomfortable with the abbreviation SS (projecting nazi connotations), just like they pushed SuMo because they're uncomfortable with SM (projecting sexual connotations).
>SwSh
The only valid way to abbreviate the two games. Based on the 3rd format, just under different circumstances than DPPt. Also, it doesn't take any more keystrokes to type than B2W2, so stop using that as an excuse.
