I realize no one's posted in this thread for a while, but I do have something to say regarding this idea.
For starters, yes I'd like to see an android appear in a Predator movie. And it could be set on earth. It could be an opportunity to see how our planet is like in the future, without requiring that it be invaded by Aliens.
If an android did appear in a Predator movie, then I believe they should wait until much later during the movie to reveal that there are even any involved. And when they do, one of them should be the protagonist himself/herself. We could find out when a Predator attacks the protagonist and we see the classic white fluid coming out of it, after surviving an injury that would have killed a human. Like say, Blaine's.
I know it'd bother some people, but whatever. If a movie like this was made, they could just pretend it's non-canon like they do with the AVP movies. A Predator movie set in the AVP universe, if you will.