You seem to be using words that mean one thing to mean something completely different and it's got me very confused.
A sprite is a collection of small images made to fit into a scene and work together to produce an animation. It does not refer to a single, non-animated image. Normally this is the term used to indicate a character but it can sometimes refer to objects that move, such as a ticking clock. In RPG Maker the term sprite is normally used to refer to the images to make the normal player characters and NPC's but technically can refer to images used in events or images used in battle, as long as they are animated by swapping images and not just moved around by programming.
A battler can refer to anything between a single large static front view image to a complex side view animated sprite, as long as it is an image that is used in a battle situation that is separate from the normal gameplay and used to represent one of the creatures or people battling. It can even be used to indicate a collection of opponents represented in a single image. Unless you're using XP or animated combat system, a battler does not normally refer to the player characters.
In the earlier Final Fantasy games, they used single images to represent the monster or villain, and they were pixelated but they were moved about on screen via programming. They were not sprites. In RM terms they would be considered battlers.
Rips aren't allowed to be posted but you may post a link to one as a reference if necessary.