What is the personality disorder in which a person takes on other peoples personalitys?

The personality disorder where a person takes on the characteristics or behaviors of others is known as Depersonalization/Derealization Disorder, but it is often more closely associated with traits found in borderline personality disorder or narcissistic personality disorder. Individuals may mimic others as a way to seek acceptance or approval, reflecting their unstable sense of self. However, it's important to distinguish this behavior from more typical social mimicry or empathy. For an accurate diagnosis, professional evaluation is essential.