In Qt version 5.15.0 and 5.15.1 , it is seen that the Virtual keyboard does not anchor as per the landscape (rotated) layout. This can be seen in the image attached.

To implement the QtKeyboard test application using Qt 5.15.0.
The QtKeyboards application is used  to verify the Qt Keyboard functionality on the platform.It is based on the Qt Example application for Virtual keyboard[https://doc.qt.io/qt-5/qtvirtualkeyboard-basic-example.html]

Qt QML application that supports Virtual keyboard in a Landscape format (rotated 90 degrees) with all language support

Error Logs:

bsh-80011370220000440335000000097 ~ # Qtkeyboard
QML debugging is enabled. Only use this in a safe environment.
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
qrc:/content/AutoScroller.qml:104:5: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }
qrc:/content/AutoScroller.qml:99:5: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }