Any guess on final coloring?

I can't read this with out pics!

 

Are you saying your chicks are the offspring of an Isa Brown crossed with a SLW? If so, which is the hen and which is the rooster.

Or are you saying that the offspring of ISA Browns and SLW are the parents of your chicks? If so, again do you know which was the rooster in the first cross between the ISA Browns and SLW? It makes a difference. Or maybe the hens are from this cross and the new rooster is something else?

The ISA Browns are already a cross between a RIR rooster and a Rhode Island White hen, so you will get mixed results from crossing them with anything else. They have lost the ability to be the parents of sex linked chicks. I think that may be your real question.

 

It is probably a little early to be able to tell with any assurance whether any are male or female but some clues may be showing up. With the Wyandottes and their rose comb in the mix, going by comb development is probably not the best method. I've never had Wyandottes so I'm not sure how those combs develop. I think being able to tell roos from pullets, especially at a very early age like this, is more of an art than a science. These are the clues I use. These are just clues. None of them are clear, sure, absolute proof. Different chicks develop differently.

Wattle development is something to look for. The roos' wattles should develop earlier and be darker in color.

I look at leg size. Roos normally have heavier legs.

Body configuration. Roos are usually more upright and maybe blockier. This works better when they are all the same breed. With them being crosses or possible crosses, this is probably not as reliable, especially early on.

When they get older, roos will have pointed hackle and saddle feathers. This doesn't usually help me until they get quite a bit older, but some people seem to be able to use this fairly early. Don't suggest new glasses. I just got some.

With even the possibility of one of their parents being a cross, color means nothing.

Sometimes nothing stands out but one will just look like a roo or look like a pullet. That is just experience.

Behavior usually does not mean anything. Both pullets and roos willl square off and fight, will run/fly across the brooder, coop, or run, and will peck at each other.

I think you are still at least a week away from being able to make very good guesses. I can usually sort of tell some of the roos at 4 weeks, but some are slower than that to develop. Usually around 6 weeks I have good confidence in saying, this is a roo, but less confidence in being sure that a certain one is truly a pullet. Some roos are just slower to develop. Some breeds are easier than others too. I have more trouble with Orpington than with Delaware, for example. They just develop differently. As I said, more art than science, and I am more scientist by both training and inclination.