Can't build a static Qml app with CMake

[I-dont-need-name]

I have a relatively simple qml app which I want to build statically for windows from Linux.

I have a rather default CMakeLists.txt file.
On the internet I found, that I need qt_import_qml_plugins() to import plugins for QML.
Adding this CMake command creates a new file in the build directory with following content:

// This file is autogenerated by CMake. It imports static plugin classes for
// static plugins used by QML imports.
#include <QtPlugin>

Q_IMPORT_PLUGIN(QtQuick2Plugin)
Q_IMPORT_PLUGIN(QtQuick2WindowPlugin)
Q_IMPORT_PLUGIN(QtQuickControls2Plugin)
Q_IMPORT_PLUGIN(QtQmlPlugin)
Q_IMPORT_PLUGIN(QtQuickTemplates2Plugin)
Q_IMPORT_PLUGIN(QtQmlModelsPlugin)
Q_IMPORT_PLUGIN(QtQmlWorkerScriptPlugin)
Q_IMPORT_PLUGIN(QMultimediaDeclarativeModule)
Q_IMPORT_PLUGIN(QtQuickControls2ImagineStylePlugin)
Q_IMPORT_PLUGIN(QtGraphicalEffectsPlugin)
Q_IMPORT_PLUGIN(QtGraphicalEffectsPrivatePlugin)
Q_IMPORT_PLUGIN(QtQuickControls2MaterialStylePlugin)
Q_IMPORT_PLUGIN(QtQuickControls2FusionStylePlugin)
Q_IMPORT_PLUGIN(QtQuickControls2UniversalStylePlugin)

But when I run make I get a wall of undefined reference errors like:

/home/user/git/mxe/usr/bin/i686-w64-mingw32.static-ld: /home/user/git/mxe/usr/i686-w64-mingw32.static/qt5/qml/QtQuick.2/libqtquick2plugin.a(plugin.o):plugin.cpp:(.text$_ZN14QtQuick2Plugin13registerTypesEPKc[__ZN14QtQuick2Plugin13registerTypesEPKc]+0x12): undefined reference to `QQmlWorkerScriptModule::registerQuickTypes()'
/home/user/git/mxe/usr/bin/i686-w64-mingw32.static-ld: /home/user/git/mxe/usr/i686-w64-mingw32.static/qt5/qml/QtQuick.2/libqtquick2plugin.a(plugin.o):plugin.cpp:(.text$_ZThn8_N14QtQuick2Plugin13registerTypesEPKc[__ZThn8_N14QtQuick2Plugin13registerTypesEPKc]+0x12): undefined reference to `QQmlWorkerScriptModule::registerQuickTypes()'

All of them seem to arise from Q_IMPORT_PLUGIN Macro (or whatever it is). What am I doing wrong? Any help much appreciated.