There is a misprint in the Aercus Instruments WeatherMaster manual - you are incorrectly advised to calibrate your wind direction in the Southern Hemisphere - this is not necessary unless you wish to orientate your sensors array other than with the embossed arrow pointing north
There are two approaches you can take with this:
1) Since the solar panel is flat to the top of the device, it doesn't really matter what the orientation of the body of the outdoor sensors is at our latitude. If you rotate body of the sensor so that the arrow marked North points North, this is the quick and easy way of getting wind direction right.
2) Alternatively, you can point the wind sensor to North and tape it in place. The you can apply a calibration in degrees to reflect your choice of orientation on the calibration screen described in 4.11 of the manual. Remove the tape, and you are done.
The Current version of the manual can be downloaded from https://aercusinstruments.com/content/manuals/Instruction-Manual-for-WeatherMaster-Aercus-Instruments-E-V1.2.pdf