All we can see of Aqua's clothes in the 1st picture is 2 red straps... the same ones Terra is wearing over his shirt.
And as for the shadow, to me it looks more like Riku. I know that makes no sense, since Riku was like 6 at the time, and I'm not saying it is him, but the shape of the hair and the clothes makes me think of Riku with the blindfold when he was fighting Roxas.
Edit: Actually, looking at it again, it also reminds me of Organization member XIV. Not the hair obviously, but the frame. As I said, it kind of reminds me of an Organization coat.
And as for the shadow, to me it looks more like Riku. I know that makes no sense, since Riku was like 6 at the time, and I'm not saying it is him, but the shape of the hair and the clothes makes me think of Riku with the blindfold when he was fighting Roxas.
Edit: Actually, looking at it again, it also reminds me of Organization member XIV. Not the hair obviously, but the frame. As I said, it kind of reminds me of an Organization coat.