What’s to stop you from accepting money from someone and giving them access to your account?
As you mentioned, you already bought some files with this account, giving someone else access to your account would be like sharing those files (in this case you actually want to sell them together with your account), and that’s not allowed.
So the answer would be, no you can’t sell it.
If someone were to buy that account the question is how much are you gonna sell it. do they need the items that you bought from envato? If I were to buy that account for lets say $100 I’d rather buy something else on that i like on envato.