Currently there are 18 native Standard Zoom lenses for Panasonic G9 and all of these lenses are autofocus (AF) type.
G9 also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on G9.
Since Panasonic G9 has environmental sealings (Weather Sealing), you may like to couple your camera with one of these 9 Standard Zoom lenses with Weather Sealings.