Is the repentance of one who slandered those who wronged her accepted, and is there expiation upon her for that?

The door of repentance is open for every person, no matter how great their sins, as long as the sun has not risen from the West and death has not overtaken them. Allah has promised forgiveness of sins and the changing of evil deeds into good ones for whoever repents, believes, and does righteous deeds. Regret is the greatest pillar of repentance. Repentance is valid with sincerity, abandoning the sin, regretting it, and resolving not to return to it. If the sin involves a right of another human being, such as backbiting, then one must seek absolution from the wronged person, unless that would lead to a greater harm. In such a case, general seeking of forgiveness and increasing good deeds will suffice.