Probably yellow legged male.
If any sex-linked genes are involved, that would be the more useful direction.
And if there are no sex-linked genes involved, then the direction won't matter.
Also, it may be easier to find good males, just because so many people want hens :)
Yes.
If you do not get any yellow legged offspring, then take some of what you do get and cross them to a yellow legged bird and you should get some with yellow legs in that next generation.