its hard to tell as my roos was bigger then that at 8 weeks but it was a standard but the waddles dont look very big eathier on your bird i would say with luck that is a pullet but the comb is a little dark so it still can be a roo, sorry i wasnt much help
My OEG Bantams at 4 weeks it was very clear who the roos were. At 8 weeks they have well defined pointed hackle and cycle feathers. The only breed I can think of that has pullet feathering is sebrights but I don't know what they look like at 8 weeks.