alteregoism
/ˌɔltəˈrɛɡəʊɪzəm/Definitions
1. noun
A tendency or practice of adopting an alternate or idealized personality, often as a means of coping with stress or anxiety.
“Her alteregoism was evident in her multiple social media personas.”
2. noun
The quality or state of having an alternate or idealized personality.
“The artist’s alteregoism added to her enigmatic stage presence.”