I am struggling with Jetson TX2 board (aarch64).
I need to install python wrapper for OpenCV.
I can do:
$ sudo apt-get install python-opencv
Another problem can be that the python version you are using is not yet supported by opencv-python.
E.g. as of right now there is no opencv-python for python 3.8. You would need to downgrade your python to 3.7.5 for now.