@chris1092387456 could it be possible you have mixed Qt versions from the one you cross-compiled and the one it's used by the OpenCV install script you used.
Assuming you run Ubuntu/opencv_latest.sh which in turn calls opencv_install.sh and then dependencies.sh, there are some apt-get install calls, so you''ll end up having pre-built Qt libraries along with your cross-compiled ones...
function install_dependency {
echo "--- Installing dependency: $1"
sudo apt-get -y install $1
}
...
install_dependency libqt5x11extras5
install_dependency libqt5opengl5
install_dependency libqt5opengl5-dev
So may I suggest to start from scratch?
First I'd follow the mechatronics guide to cross-compile and deploy Qt in the RPi device.
Then I'd follow this guide to cross compile the latest version of OpenCV for Raspberry Pi. As you'll use WITH_QT=ON flag I guess, please adjust the paths in the CMake script(s) to use the cross-compiled Qt version in your host PC.
And also use the correct path for cross-compiled OpenCV in your .pro file. As example, the following doesn't look good to me:
LIBS += -L/usr/local/lib/libopencv_highgui.so
