How do I replace QXmlQuery and QXmlFormatter in QT6

Question

The xmlpatterns module gets removed in Qt6 and how can I rewrite the code below:

We use QXmlQuery and SchemaMessageHandler, m_queryContent is an xquery file use variable defined in nuiBuffer and metadataBuffer:

QXmlQuery query;

SchemaMessageHandler messageHandler;
query.setMessageHandler(&messageHandler);

//Bind the content of the NUI to an XQuery var.This way we can reference
//the nui from within our query
QBuffer nuiBuffer;
nuiBuffer.setData(m_nuiContent.toUtf8());
nuiBuffer.open(QIODevice::ReadOnly | QIODevice::Text);
query.bindVariable(XVAR_NUI, &nuiBuffer );

//Bind the content of DevtoolsMetadata to an XQuery var.
QBuffer metadataBuffer;
metadataBuffer.setData(metadataContent.toUtf8());
metadataBuffer.open(QIODevice::ReadOnly | QIODevice::Text);
query.bindVariable(XVAR_METADATA, &metadataBuffer);

//Set the query
query.setQuery(m_queryContent);

QBuffer resultBuffer;
//metadataBuffer.setData(metadataContent.toUtf8());
resultBuffer.open(QIODevice::WriteOnly | QIODevice::Text);

Then we use QXmlFormatter format the xml string:

//We need to maintain the same format with uiDesigner
QXmlFormatter formatter(query, &resultBuffer);
formatter.setIndentationDepth(FORMAT_INDENTATION_DEPTH);

//qDebug() << "XQuery Expression:  " << m_queryContent ;
if (!query.isValid()){
    qCritical() << QString("Invalid query. Error at line %1, column %2").arg(
                       messageHandler.line()).arg(messageHandler.column());
    qCritical() << messageHandler.statusMessage();
    return false;
}

if (!query.evaluateTo(&formatter)){
    qWarning() << QString("Runtime  query error at line %1, column %2").arg(
                      messageHandler.line()).arg(messageHandler.column());
    qWarning() << messageHandler.statusMessage();
    return false;
}

m_queryResult = QString::fromLocal8Bit(resultBuffer.data());

Need to find a way to replace QXmlQuery and QXmlFormatter