undefined reference qt_static_plugin_QtVirtualKeyboardStylesPlugin()

Hello,

I use a static cross-compiled QT-Version 5.9.2 on x64 for armv7-gnueabihf (imx6).
My QMake-Configuration: (config.opt)

Code:

-commercial
-debug
-static
-no-compile-examples
-no-pch
-nomake
tests
-nomake
examples
-prefix /opt/qt59
-hostprefix /opt/qt59
-device
linux-imx6-g++
-device-option
CROSS_COMPILE=/data/fslc-fb-sdk/sysroots/x86_64-fslcsdk-linux/usr/bin/arm-fslc-linux-gnueabi/arm-fslc-linux-gnueabi-
-sysroot /data/fslc-fb-sdk/sysroots/armv7at2hf-neon-fslc-linux-gnueabi
-no-xcb
-opengl
es2
-skip
qtwebengine
-eglfs
-tslib

In my Application, the QtVirtualKeyboardPlugin is used.
My Project-File:

Code:

QTPLUGIN.imageformats = qsvg
QTPLUGIN.bearer = -
QTPLUGIN.qmltooling = -
QTPLUGIN.platforminputcontexts = qtvirtualkeyboardplugin

If I remove QtVirtualKeyboardPlugin, my application will be compiled an will run on target successful.
If I add QtVirtualKeyboardPlugin (+ functionality), my application will not compile.
The following error messages will occure:

Code:

opt/qt59/plugins/platforminputcontexts/libqtvirtualkeyboardplugin.a(plugin.o): In function `QVirtualKeyboardPlugin::create(QString const&, QStringList const&)':
plugin.cpp:(.text+0x6b8): undefined reference to `qt_static_plugin_QtQuickLayoutsPlugin()'
plugin.cpp:(.text+0x7a8): undefined reference to `qt_static_plugin_QtQuickLayoutsPlugin()'
plugin.cpp:(.text+0x7d8): undefined reference to `qt_static_plugin_QmlFolderListModelPlugin()'
plugin.cpp:(.text+0x8c8): undefined reference to `qt_static_plugin_QmlFolderListModelPlugin()'
plugin.cpp:(.text+0x8f8): undefined reference to `qt_static_plugin_QtVirtualKeyboardStylesPlugin()'
plugin.cpp:(.text+0x9e4): undefined reference to `qt_static_plugin_QtVirtualKeyboardStylesPlugin()'

What I am doing wrong?
Thanks for tips/tricks,