Is it permissible for the owner of a women's clothing store to send pieces to women on social media for them to display and promote, knowing that the work of these women is to display clothes and they do not wear a [proper] Shar’i hijab, and that there is a possibility that men may see these images?

It is permissible for the owner of a women's clothing store to send clothes to women who display them on private women's websites that men do not view, provided that their bodies do not expose what is impermissible for women to expose. If a man happens to view the display by chance, there is no sin upon the store owner.