Daughters of the nations is a common enough expression for the nations themselves, but is peculiarly appropriate in connection with a lamentation, since the formal mourning of the East was always performed by women.
Related Commentaries of Ezekiel 32:16
Ezekiel 32:16
16 This is the lamentation wherewith they shall lament her: the daughters of the nations shall lament her: they shall lament for her, even for Egypt, and for all her multitude, saith the Lord GOD.