Actually, I have one I found online that does loop in the MZ editor. I've left it playing for minutes at a time just to see if it looped infinitely, and unless it's set to run for an excessively long amount of time, pretty sure it actually loops without any input after hitting the play button in the editor. I tried to replicate its settings in the Effekseer editor with your aura animations as best I could, and it didn't work. The looping one isn't based on a sprite sheet, so there might be something the typical MZ animations can do which sprite sheet animations can't. Regardless, animations looping while playing in the editor is possible, so I figured I'd ask about it.