If you're absolutely sure about her age as 6 months, then I believe her to be a pullet. Does she have silkie heritage? She's got blue earlobes. If she's 5 months or less, I sat Roo. True Polish hens usually have little to no wattle and comb.
Im 76% positive on her age. The blue earlobes are odd and ive wondered about them. She looks just like my buff rooster in almost every aspect except a little smaller and the blue ear lobes.
On the blue earlobes all my hatchery polish I got last year 75% had blue ears. Which they aren't supposed to be, they are supposed to be white by the breed standard.
Definitely a pullet getting ready to lay. If you had a boy, he would have streaming feathers coming out of his head and have saddle feathers and hackle feathers streaming as well.
She is pretty, I do love that color, but I have decided that Polish and I don't get along so well.