Olive eggers can look like anything. The one on the right looks more like a black sex link, and the one on the left might be an olive egger. I guess you'll know when they lay.
At 16 weeks, cockerels would show male specific feathering, and there is none.
Lavender Orpingtons can be variable in color as chicks. I can't think what else they'd be because there aren't any other lavender varieties on Hoover's website.
All are pullets. The lavenders are Orpingtons, you are correct about the Prairie Bluebell egger, and I think the red one is a Calico Princess or similar hatchery hybrid.
*I believe the red one is a Hampbar after looking at Hoover Hatchery's website.
I agree with Pigeony. Wing sexing only works for hybrids specifically bred for that trait, like Amberlinks. It's not going to work here. It's really all about the combs and wattles when they are young, both the color and size.