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KD
Since: May, 2009

What is the trope for someone who has a split personality, but can converse with their alters?
In Moon Knight (2022), Marc and Stephen are able to converse with each other through their reflection in the mirror.
Also, in JoJo's Bizarre Adventure: Golden Wind, Doppio and Diavolo can talk with one another over "telephone" (ie. any object small enough that one could hold it up to their ear and pretend its a phone).