How to migrate from QtScript to QJSEngine?

Question

Qt

I've been using Qt for a long time, I like everything cool, with the release of QJSEngine, QtSctipt was marked as obsolete,
but I still can't transfer some functionality to QtScript.
There is some platform using QtScript as a JavaScript interpreter to describe application logic.
JS script example

var f=new File('/var/www/test1');
f.write('123\n');
f.CopyTo('/var/www/test2');

The File object is described as

class File: public QObject, QScriptable {
Q_OBJECT
….
}

and there are more than 20 such objects described in the platform, a lot of logic is embedded in their constructor / destructor, there are Q_INVOKABLE methods that are called in JS.
The question is: how to transfer all this to QJSEngine while preserving the syntax of the JS code (it has already been written a lot)?
I was looking for answers on stackoverflow
Dynamic creation of c ++ objects in QJSEngine
Transition from QtScript to QML/QJSEngine
Dynamic c ++ object in QJSEngine
It is suggested to do it through the factory, but this will greatly impair the readability of the JS code and it will have to be rewritten.