There is an “empty-vacuity”, that of beings and phenomena that are svabhāva-śūnyatā, i.e. empty of their own nature, not existing by themselves and, ultimately, illusory and impermanent. This emptiness is therefore not nothingness at all, but simply a reminder that “all phenomena are merely conceptualizations and are devoid of their own nature”.
To say that Ultimate Reality is Vacuity has a different meaning. It is ’empty’ only of all materiality and all that can be conceived of it; it is a “Vacuity-Plenitude”.