If you want to move your project to another account you need to open your Applications page.

Open context menu and click on "Move" link.

Tile view:

List view:

On the next page you need to enter Account ID, that will receive the project.

You can find Account ID on the Account page, "Others" tab:

Please note: when you move an application to another account, the app's export log is moved too (export log belongs to the project). It can affect the account limits.

You can view the export log on the "Account" menu, "Payment and Statistics" page.