What is the punishment for someone who slandered her colleague, tarnished her reputation falsely, accused her honor untruthfully, called her a "street girl," and photographed her without her knowledge? And is it permissible for the wronged person to do to her as she did to her?

If women speak about you with what is not true, then it is slander (buhtan), and it is worse than backbiting (gheebah). If their words reach your honor, then it might lead to calumny (qadhf), as Allah Almighty says: "And those who harm believing men and believing women for [something] other than what they have earned have certainly borne slander and a clear sin" [Al-Ahzab 33:58], and His saying regarding calumny: "And those who accuse chaste women and then do not produce four witnesses - lash them with eighty lashes and do not accept their testimony ever after. And those are the defiantly disobedient" [An-Nur 24:4].

It is not permissible for you to treat them in kind, but you have the right to defend yourself and to refer the matter to the responsible authorities to deter them.