Authors may unofficially partner with other authors to create new items, but we advise strong caution when doing so. Envato Market considers the person who created an account and agreed to the terms and conditions to be the sole copyright holder of the items for sale and the only person eligible to withdraw any funds.
You are certainly free to partner with another author to create items for sale, but please keep the following important point in mind. Envato Market enters into a legal agreement with the person that creates the account. For example, if the name John Doe is signed up, then John Doe is the sole individual Envato Market has an agreement with, and this is the person who owns any earned funds in the account as far as Envato Market is concerned. Only one person's name can be used.
You are more than welcome to come to a private agreement about the account and its earnings of your own accord, but we cannot get involved in any dispute or issues. We will only issue payment out to the account holder and their nominated payment details.