Hm, the special thing in this situation is the getProperty() which is (why ever) not there as an OOB action in Flow Designer. But you could easily create it as a scripted action. If you create it with a flexible input parameter, you can retrieve both properties one after another with the same action, and then use a simple If, using the outputs of both steps to go on with your flow. If you need this more often, you can even put that sub logic (retrieve both properties, and return either true or false) into a reusable Subflow.