You need a plugin. Shaz made a good one here: https://forums.rpgmakerweb.com/index.php?threads/change-battle-mode.46742/
Very welcome. If this solved your question, then if you didn't already, click "report" on your first post and put in the reason box something like "this thread can be closed now."
No. What he means is changing it in the game, like having SV battle in the game SOMETIMES, but not always.
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