Any idea on the genders?

[SelfSufficientMe]

All looks to be pullets and they actually appear to be poorly marked splash. Gray in silkies is actually silver partridge and you’ll see a gradient of color going from the head down to the body and usually some penciling on the wings.

Up close view of fluff pattern/coloring

 

[LadiesAndJane]

Up close view of fluff pattern/coloring

Yours are Splash. A grey (silver partridge) looks like these 2. They can be more grey, but sometimes have some brown going on, too.

Photo of my splash hen, she looks much like yours.

 

[LadiesAndJane]

The confusion is that in the chicken world gray chickens are called blue. Splash is part of blue/black/splash genetics.
Gray or silver partridge is a whole different color.