If possible at all, it is complicated .. and my idea could be wrong.
The powerfractal itself is 3 dimensional (best to be seen on the clouds),
stretching the noise along XZ will create respectivly 'flat' clouds.
As there is no detail added, you should first of all rather compress the fractal along Y (using values between 0 and 1).
Now comes the tricky part, that I never played with, yet ... inside the function-nodes you have two interesting categories: Convert and Rotate.
I assume that you use the PF as a scalar output (shades from black to white), so you would need to convert that scalar to a vector (which can be rotated with the other set of nodes).
In fact I doubt that it is possible at all ... maybe you do not get any result - or you get some results you would like to share with us ,-)
Volker