Unfortunately no. The developer of RGM never implemented idle animations on sprite objects.
You can have 4-frame animated wall textures. And you can make enemies stationary so that you can create projectile turrets or things like that. The problem is that stationary enemies use a 0 in the speed parameter, so that means they aren't moving, and so they won't actually play their walking animation while at rest.
Sprites can be destructable, so they will play 5 frames of a death or destruction animation. But unlike the wall textures, sprites don't have an option for a 4-frame idle animation.
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I just discovered how he did it: the maker somehow managed to turn non-moving "enemies" in animated NPC characters. Unfortunately he is no longer active in game development. The only issue I now have is white borders at the edges of my sprites but that's a matter of trial and error I guess, thanks again.