Like primalspas said, Genetics isn't always so simple. What would most likely happen is that an offspring of the Uchiha and Hyuuga clan would have some aspects of both eyes but not fully powerfull. This offspring may have a very wide field of vision, but it wouldn't be nearly 360 degrees. The offspring would also have some ability to copy, but wouldn't be able to do it as well as a full blooded Uchiha.

That's just my opinion; I could be wrong.