There is no definitive answer to this question as it depends on the specific laws of the country in which you are selling your account. However, generally speaking, selling an account through a digital platform such as Steam or the App Store is generally considered to be a form of online gambling, and therefore is not considered legal in most countries. If you are unsure about whether or not selling your account through a digital platform is legal in your specific country, you may want to consult with your local legal authority.