I had a daughter like that, and at that age, although she didn't have any other children to wind up. If she behaved like that I just ignored her. I was the adult in this situation and was not going to be manipulated by a child. Do not negotiate with her, do not tell her how much she is upsetting you or act or look upset. Just get on with what you want to do and if necessary turn your back on her and walk away, not far enough to put her in any danger but enough to show her that her performance is a waste of time as she doesn't have an audience
Once DD knew I wouldn't take any notice of her and was not impressed by her behaviour and had absolutely no intention of giving way to it, she didn't stop completely she was smart enough to realise that keeping an element of it going would always be an irritant, and completely giving it up would lead to her loss of face, but she did realise that I was in charge and wasn't handing over to her any time soon, nor was I impressed or intimidated by her behaviour.
I fully understand how you feel. It is exhausting, and you constantly have your temper under tight control, because you know she is trying to wind you up to make you do something to put you in the wrong and you musn't do it.
She is not too old for this behaviour, nor is there anything wrong with her. She is just a very very strong willed girl determined to have her own way all the time and make life difficult for everyone who doesn't do as she wants.
I once to say to my daughter 'Only one of us will reach your 18th birthday, you will be the death of me or I will be the death of you.
Although I didn't have any dividing and ruling with other children, perhaps you could when you get home from any outing with her, be prepared to gather the other children round you to do something interesting, so that she can not gather them together round her. After shopping etc what about drink and biscuits all round, or read a book together, or anything else you can think off.
The only consolation I can give you, is that mine has grown into a lovely kind thoughtful adult, who because of her strength of character and determination has made a really good career for herself and has lots of friends.
The one interesting thing is that she has chosen to neither marry nor have children because, as she herself admits, she is far too uncompromising to ever manage to share a home with anyone, but she dotes on her niece and nephew, and is part of a loving family and we are all proud of her achievements.
But if you want to PM anytime do, I really understand what you're going through, but there will eventually be light at the end of the tunnel.