The two inner sensors are a different part number because they have a different shape (connector plugs in in-line with the sensor, as opposed to a 90 degree bend)
Inner sensors: 3C0919275AD (this is a supercede part number)
Outer front and all rear sensors: 3C0919275S.

You can get to the inner sensors and swap them over one side for the other easy enough by removing only the top of the inner grill and holding it out while you fish in for the sensors.
The outers however require removal of the front bumper. It's not too bad but there are 4 nuts in behind the front wheel arches that are a long reach with a deep M10 socket.

You can buy them second hand from Europe pretty cheaply on Ebay etc.
Or Chinese ones of the correct part number for like $10 each. Can't vouch for their quality personally as I haven't used them.
If you can't find them in the correct colour they are very easy to paint just get a can of colour matched spray paint from Supercheap or wherever.

I have a can of Biscay Blue and a can of clear you're more than welcome to make use of for the outers.