Although gender change has always been allowed on World of Warcraft, players will have to pay $15 to change their gender but that will no longer be the case when the new expansion, Shadowlands arrive.
According to John Hight told Eurogamer that players will be able to go to the barbershop now and get their appearance and gender change. He added that playing to change gender did not carry the right message but added that updated it is not as easy as it seems as it cannot be fix with a hotfix which is why it will only be arriving with the expansion.
We are not sure if only those with the expansion will get to do this for free or if the update will be available to all players. He also discussed the forum talks about some characters being made as trans and acknowledge that it was likely the intent of the designers.