What sex are these?

they are both pullets...with d'uccles you can tell cockerels and pullets apart at 3+ weeks  combs are small on both of them as well

#1 definitely a pullet. #2 pretty sure its a pullet if thats a single comb on her head and not a pea comb 

D'uccles are VERY easy to sex, by a month old the boys have a prominent and red comb on their heads while the girls stay pinkish until much much later. If #1 was a boy at 3.5 months old then she'd have a full blown roo comb and bright red face. the reason you think your seeing pointy hackles is because she has penciling/lacing in those feathers, it makes the feather appear pointed, especially in a group of laced/penciled feathers. 

#2 are you sure its a silkie mix? I don't see anything about the bird that screams silkie at all....I would expect much darker skin, and atleast as light tuft on the head since silkies are crested, even my d'uccle X sultan mix has a slight raise on the back of his head behind his comb... 

Here is my d'uccle X silkie hen (old picture she was about 4-5 months old in this picture)

favorelles and Sultans are 5 toed breeds. sultans have feather feet and I think favorelles do too. D'uccles can have dark skin, but not black. Do you see Corvette's (my picture'd girl) her toes in that picture? that is black skin on a chicken...is your girl's feet/legs that dark? is her body dark skinned as well? if so then yes she does have silkie in her, I just don't 'see' it - lol. 

I have bantam hens who boss and attack standard size roosters. - she is rejecting him - thats why she attacked him. did you put her in his pen or him in her pen? 

Trust me if thats a single comb (which it appears to be) on #1 - its all female.  if she is 3.5 months old, shes not ready to be put in with a mature rooster who will attempt to mate her. If the boy is a young cockerel around her age, shes just bossing him in his place as shes a dominant girl. If they are the same age - you can put them together, just keep an eye on them and make sure the fighting doesn't get too bad - but nitpicking and a bit of fighting is normal til they get used to each other. Its best to put her in his pen or remove both from a pen for a couple days and put them in together at the same time, this puts them on equal ground and makes it a bit calmer atmosphere for them to get used to each other. 

Yes, you've got a couple of pullets on your hands.

Females.