Minecraft Optimized for S/X……..,

Because on my Xbox series x, it only shows 'Optimized for series x/s' but if a xbox series x version of a game is NOT 'optimized' how would i know if I'm playing a series x/s version of a game?

It's optimized for the Series S/X, but there's not a separate version for the One and Series S/X. So it'll work.

Here is a list of the optimized games for series XIS: Optimized for Series X|S | Xbox

Are you using a Series S/X?

Series S/X optimized games can only run from the internal SSD or an expansion card made specifically for the Series S/X.

Yes you can. The expansion card is for Series S/X optimized games. So you should be able to run any game from them as opposed to regular external hard drives which cannot run Series S/X optimized games.