Yes, many, always have.
Awkward when in a group and some people know me differently to how others do.
I have always found it necessary and still do.

Nope....I may be quiet and limit chat to weather or sports at work but anytime patriarchy, war crimes or theocracy comes up I blast away for bullseyes

What you see is what you get but I admit once every decade or two I may get pissed and you may not survive me pissed.

I do alter speech and mannerisms to fit the occasion occasionally, but I'm what you get in real life or online.

I had a nervous breakdown at 17 and went back to the world after treatment not having the slightest idea who I was or who I should be. The only thing I knew was that the person I was did not have a place in the world. In less than a year I tried to do away with that person. For more than 40 years after that suicide attempt, I tried umpteen different versions of me and as you probably suspect, none of them worked any better than the person I vaguely remembered from the past. I’m old now and virtually retired so I don’t need to project a persona anymore. That means that I can be myself. The trouble is that I don’t know who that is.

I am different around my family and my coworkers mainly because of religion and political differences. They all know my choices but I tone myself down so as to not alienate them. It is refreshing to be around people who understand what I have gone though in reinventing myself and it is nice to be commended for critical thinking rather than criticized for it.

I'm pretty darn professional while at my day job so I probably come across as straight laced. Other than that no.

I tailor my speech & behavior for the setting & situation. If the real me went to work, I would not have a job very long.

This happens to people with EUPD who rarely understand who they really are. There is no grand discovery following a series of soul searching therapy, often the damage is done...they have to create a new real them. It is tough but doable. 'Fake it til you make it'

Nope, actually this "IamNobody" is becoming a full time job !!!...no time for more than one parallel universe. Just like anybody else with a bogus identity, I do have a real life, and my other life on Facebook...etc...etc..etc

Ummm not sure if I understand the question. Do you mean profiles? Such as having profiles that differ for various sites. Or do you mean in life where one puts on different hats depending on the social or work environment. I consider myself complex or perhaps multifaceted so I'm lots of things and I think it takes people a long time to really understand all of the facets another person presents.