can a girl dress up as the 80s boy george

A girl can dress up as anything she damn well pleases.

Why not? It would be easier and more accessible for a girl to dress up like Boy George then for a boy to pull it off.

Just curious: Would this be a lifestyle choice, a fashion statement, or a costume to temporarily inhabit?

Why would you want to?

I'm going to guess that her school is going to have an 80's theme dance party but then again I could be wrong.

Boy George dressed up as a girl. Why not?

When Boy George went on a world tour in the 1980s, when he was a successful pop star, (before he became a criminal) wherever his plane touched down the airport would be packed with crowds of hysterical girls all identically dressed and made up like him.