Sisko was half wormhole alien.
No he is full human although who knows the Aliens could have made some modifications they are far more advanced then the federation. Although that really is a complicated Story.
Still the answer no never going to happen. At least as the main in a show. Now if they are near human like a Trill, Betazoid, or a Vulcan sure but straight alien no best odds there are a Klingon and they are still fairly near human.
I agree an Asian (anywhere from Saudi Arabia to Japan is fine) and some from South and Central America is a good idea.
Honestly, thing I liked about Voyager was high diversity.