What about my guests?
Today the solution is pretty easy - forget about traditional power outlets and go with the new default standard for charging gadgets - USB.
You can install power outlets that have USB ports too.
You can cost effectively retrofit power outlets at desk height with USB only or a combination of USB and power.
Make sure your clock radio has a USB Port for charging devices.
If you provide a Connectivity Panel, make sure it has a USB port for charging too.
International and domestic guests will be thrilled by all the charging options you provide them.
If you want to go down the traditional power outlet option, you can still provide a universal travel adapter - make sure it's approved - it needs to meet Australian/New Zealand Standard AS/NZS 3122:2005. If it is approved, it will have a fixed 'single state' Australian plug that goes in the outlet and the universal component may be 'single state' or adjustable to accommodate multiple plug types.
Keep in mind, the guest needs to ensure that whatever they plug in can handle Australian power. These days many laptops and other devices with transformers can cope but the guest should always check. Most small personal grooming items like hair dryers, hair straighteners CANNOT cope and will at the very least be seriously damaged if not cause injury to who ever plugged it in and even start a fire.