I had the same kind of problem, but needed to check this slightly different list:
pacman -Qo /usr/lib/qt/qml/QtQuick/Controls/*.qmlc
pacman -Qo /usr/lib/qt/qml/QtQuick/Controls/Private/*.qmlc
pacman -Qo /usr/lib/qt/qml/QtQuick/Controls/Private/*.jsc
pacman -Qo /usr/lib/qt/qml/QtQuick/Controls/Styles/Base/*.qmlc
pacman -Qo /usr/lib/qt/qml/QtQuick/Controls/Styles/Desktop/*.qmlc
pacman -Qo /usr/lib/qt/qml/QtGraphicalEffects/*.qmlc
pacman -Qo /usr/lib/qt/qml/QtGraphicalEffects/private/*.qmlc
They all got ‘No package owns’, so I deleted them.
Thanks to thefallenrat for the clue.