Duck wing seems most likely, as long as it is silver/grey, not a reddish tan color, I can’t tell for sure from the picture. They are fairly easy to sex, The cockerels with start developing color in their wings/back while the pullets with primarily only develop the lighter color in their hackles, which should be coming in soon!Just by way of an update, Here’s one of our wee ones at 4 weeks—a duckwing? When should i be able to sex them?
I have a batch of 3 week old moderns, and can see some lemon feathers already popping up in the back and shoulders of two that I can now name cockerels.