Suggestion: When reviewing matches that have already ended, there could be an option for the Pokémon on your opponent's team to remain hidden, as if it were the first time you were watching the replay. This is how replays normally work, and having this option could help maintain the surprise for anyone who is recording content about the match and wants to let the Pokémon be revealed as the match develops. Of course, leaving it as an optional button to reveal or not reveal the six Pokémon from the first turn of the game, anyone would be free to choose to leave them revealed (as it currently works) or not revealed (my suggestion).
I suggested it as a double option (reveal or not reveal) because I think it would be better to have both options instead of just one.
So, if you revisit a battle that's already over, there could be somewhere for you to choose the option you want at the time (not necessarily in the corner I suggested below). It could be another way too. The idea is to have both options.