Covey's book contains a lot of common sense if one wants to be effective in one's projects and dealings with others. But is it ethics ? Specifically is it a form of virtue ethics ? This is the highly interesting question you raise.
A moral virtue, as the term is widely understood, is a habit capable at least within limits of voluntary modification. All Covey's habits embody these features of virtue. But there is more to a moral virtue than merely such a habit.
One moral virtue that is implicit in Covey's list is that of self-control, what the Greeks called sophrosune and our ancestors called 'temperance'. Impulse, desire, acting on casual inclination, are held in check, subordinated to the self-control that is essential to personal effectiveness.
Probably courage, another moral virtue, is presupposed to Coney's list. The effective person, as Covey envisages him or her, will need the capacity to face and overcome obstacles in the carrying out of projects - not least those obstacles created by other people.
None of the habits, so far as I can see, is directly moral. The seven habits are all self-centred : they are a guide to how best to get what one wants out of life. There is talk of empathy but only because without empathy one will be hindered or frustrated in getting what one wants.
To be moral virtues the seven habits would have to involve seeking the good of others as well as one's own - and seeking it, not merely as a means of getting what one wants, but from respecting the rights of others for their own sake and promoting the common welfare as something intrinsically morally worthwhile. There is no recognition of any such demands of justice or benevolence in Covey's list of habits.
In other words, Covey's is a self-help book which has little or no regard for one's moral relations with other people except as instrumental to one's own ends.