Could you get a photo of the head comb area full face? I'd like to see the comb better to be sure.
I agree with the other posters, it is not a Black Sex Link for reasons given.
If it is a rosecomb (which I think it may be...hard to tell in the boundary blur)...then it looks to be a Silver Laced Wyandotte...but I would not call this a male yet. The color pattern is still even and not blotchy, and the comb is not that big for 9 weeks. Wyandottes can be hard to sex as the males develop more slowly though....and sometimes can be hen feathered....but a lot do broadcast by 9 weeks.
If that is a single comb, then it is likely a mixed breed chicken (although some Wyandottes can have a single comb, but it is a fault and not accepted in the line)...or even a Silver Penciled Rock...or a Rock mix that colored that way...again I'm leaning to pullet.
Definitely not a Sebright...wrong body shape...Sebrights are bantam/game type birds wherein the wing tips fall below the body line. The bird would be very small too, and have a more upright stance.
You have a layer body type.
Don't worry about the large legs...I've had lots of pullets with
Amazon legs.
LofMc