I'm not sure it will work, because you already have one cross as the sire. He doesn't have 2 barring genes himself, he has 1. Therefore half his offspring, regardless of sex, will get a barring gene, because in birds the males are the homomorphic(WW) sex. The legbar will pass her barring to all...
If your sire had been the marans and your dam the cream legbar, and the marans had been a solid color or a black silver or black copper, you could have created olive egger sexlinks. I made a short video on it when I hatched a few using this combination.