finnfur
Songster
I'm by know way an expert but I would only go 70% its a cockerel - I've got some slow [not size] developers at 7 weeks that could still go either way.
You really can't be certain of coloration until first molt IMHO . I just weighed some at 5 weeks for a comparison if you want to weigh it.
14 Birds - Largest 14 Oz - smallest [Runt] 8.2 Oz and average was 11.57 oz [These are my Blue line from Kathys line.]
Bottom line is Delaware legs should be yellow, fairly bright when young and usually fading as they age/egg lay. The fading is ok, but still yellow. I have had chicks hatch with almost white looking legs from parents with yellow legs and their legs yellowed with time and free-range so I am sure in my case that feed plays a part. Have not had much experience with the green as never hatched any myself, but I have some chicks from a new line that have green, much more faded looking than your pic.