Or he just ate something wrong right before Zero Mission and Super Metroid fights with him.
All get hit animations required for serious matches without items are done, so, we are even closer! Have this for now:
This is side taunt. He steps back and then makes "Come and get some" gesture, like Captain Falcon during his side taunt, but in a more...gentle way, all of that while laughing. Then he roars like during one of the victory animations, but it doesn't lasts that long and he doesn't moves much. It shows that Ridley is both intelligent and a beast. Up taunt is nothing really special (just him roaring at the screen/background while flapping wings).