It depends on what the Legbar is mixed with.
Crested Cream Legbars have a crest, single comb, and yellow legs. They do not have muff/beard or a pea comb or legs that are blue or green.
If the CCL is crossed with other breeds that have single combs and yellow legs, the chicks will also have single combs and yellow legs, plus the crest from the CCL parent.
If the CCL is crossed with chickens that have muff/beard, or other leg colors, or other comb types, then yes those other traits can be in the CCL-mix chicks.
Because Ameraucanas have pea combs, muff/beard, and slate (blue) legs, it is common for their chicks to have those traits too, no matter what breeds they are crossed with. If they are crossed to breeds that have yellow legs, it is common to get green-legged chicks in later generations.
That is why Easter Eggers that descend from Ameraucanas often have pea combs, muff/beard, and green legs (they do not have to have these traits, but they often do). Easter Eggers that descend from Crested Cream Legbars will often have a crest, yellow legs, and a single comb (again, they do not have to have these traits, but they often do).