It's a little hard to see, but the male will develop a grey /blue color above the nostrils and female a brownish/ pink. From what I can see your green budgie is a boy and yellow a girl.
Hens have tinted blue with white,white when young adult hens have tan or brown. Males have pink,blue or purple. Looking at the pics the top looks like it could be a hen. Need a face shot to see bottom is def a male lutino his cere will always be pink.