It really isn't fair to others to offer a villager you don't have actually moved into your town yet ^^; There is a chance you can't get her and then you'd be getting people's hopes up.
I'll leave it for now since it does seem like you are going to, but keep in mind in the future we'd rather people just offer villagers that are actually in the person's town already moved in.
Similarly, if you already decided who will be getting her, it's not fair to still accept offers on it ^^; Otherwise, you shouldn't have picked already...