can color contacts cover up dialted eyes?

Answer 1

Some.
Many just have a tinted iris portion, but those which are capable of turning a brown eye blue have a more definite printed opaque periphery.
The wilder Cat's-eye and Lizard-eye type contact lenses are of this nature, but they don't have to have a peculiar colouration.

The more solid colour, however, does have a slightly poorer cosmetic effect than the "enhancer" tinted ones,
and there is a degree of restriction to the peripheral vision, depending on the size of the clear pupil, and the depth of the anterior chamber.

Optometrist, retired.

Answer 2

No. Color contacts are tinted, not opaque or you would not be able to see through them.