No, currently this is not possible. You can create another account using a different e-mail address, and invite your main email to that new account, then you will be able to switch between accounts from the account selector in your profile menu in the top bar:
Click the arrow next to your existing account and select the account you want to switch to, from the drop-down list.
Sinch has a new single sign-on login experience that will allow you to seamlessly login to any existing Sinch services that you may use - Learn more about Sinch ID.