Would this be offensive? (Please see details).

I have been playing the videogame Left 4 Dead a lot lately. It is my favorite game and what I spend a good deal of my spare time playing. I usually play Left 4 Dead 2 and my favorite character to play is Rochelle. I admit, I originally played as her because she’s the only female character in the second game, but she quickly became the only one I wanted to play as. I would love to dress up as her for a convention or maybe even for Halloween, but she is black. I want to be as authentic as possible with the costume. I was not thinking of doing blackface, because I know that is offensive. However, I was thinking of using dark brown foundation for my face and possibly my arms, depending on how much patience I have in order to look like Rochelle. Would this be offensive?

Before anyone asks, it is unlikely that the outfit would be enough. She is dressed pretty generically in the game, just a pink shirt with a logo and jeans. Just as a white girl in this outfit, people probably wouldn’t recognize me as Rochelle.