Are 3/4 Cream Legbars sexable?

[MaeIstrom]

I have a female from a CCL/hyline brown cross that I can't help but notice has the exact same dosage of the barring gene as a pure-bred CCL female if not the same coloring so my question is if bred back to a CCL rooster will the offspring be sexable? And would that mean that CCL and barred plymouth rocks could be used interchangeably to create sexable offspring? I'm also assuming the white females I have from a CCL/leghorn cross would throw 50% barred (and thus sexable) and 50% white from being bred to a rooster with double barring.

 

[Yucky_ducky_kentucky]

I think when they’re chicks the males have a white spot on their head and the females have more markings. I ordered 7 silkies recently online but they sent 2 mystery chicks and I suspect that one is a male crested cream legbar. In the pic it’s the orange chick in the very back with the spot on it head. All the rest are silkies except for the black on that could be a serama? The other pics are pictures of female and male chicks of the cream crested legbar breed

 

[MaeIstrom]

Yes I know that, the white spot is supposedly from the male having 2 copies of the barring gene to the female's 1 which is why I'm curious about the effects of using a hybrid hen or mixing barred rocks and cream legbars in regard to this white spot. Especially since I've read the Cream Legbar can lose it's auto-sexing traits if this is not vigorously selected for.
In face I have another broody with 3 (supposedly) pure-bred Cream Legbar chicks and while 2 have the traditional markings of a male the third just looked mostly black when it hatched, I assume it's female but it doesn't look like any CCL chick I've ever seen, it's the one on the far left...