A visual novel is one slide of image after another image with texts, where it can have branches with choices.HOW? How a bit of free-roam make a game not a VN? What the right tag then? ... ... ...
Take Milfy City for example, it doesn't have VN tag, because MC can move around the city during the day.
MC is not forced to jumped from last image to the next image which forms a sequence of story.