As a part of SoK project, I am currently porting device notifier applet to Plasma2. Device notifier applet was already ported to QML by Viranch Mehta so it was somewhat easy task for me. In a Plasma2 port first task is to change versions of imports and some other modifications. Result was awesome, I got Device Notifier applet in working stage.
After that I ported config.ui file to config.qml because in Plasma 2 config.ui files are no longer used. To port config.ui files you can have a look at the code given in plasma-framework/examples/applets/conditionalloader. As a sidenote all example DataEngines in the plasma-framework/examples/dataengines are now ported to use KF5.
Here is a configuration dialog which is ported to QML.
But currently other options like Device actions, Removable devices are still missing.