I feel like this is a common problem in the hobby lol I'm going to be so confused once the babies I picked up this year start producing.

I'd say based on the photos there that maybe the one on the left is pastel because it overall looks a little brighter then the one on the right. Its head also looks quite a bit brighter but it could just be the lighting. Once you get that many genes it's really hard to tell.

Don't take my word on it though haha hopefully someone who actually knows what they're talking about will be able to help you more.