I have never tried to change orientation in a VIDEO editor... always in a picture editor before importing into a video timeline
What version of Premiere Elements are you using and on what computer operating system is it running?
For now I will use Premiere Elements 13 on Windows 7, 8, or 8.1 64 bit as the example.
If you have imported landscape oriented video (which is the usual) and for some reason want to change the orientation
from landscape to portrait, try selecting the clip on the Timeline and going to Applied Effects Tab/Applied Effects Palette/Motion Panel expanded where you will find the Rotation feature there. You could also right click the video on the Timeline and select Rotate 90 right or Rotate 90 left. Are you prepared to work with image with black borders?
Just in case reference...
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