You can clone an email to another brand by going to the Studio in your account.
Click on the ellipsis on the far right side of the email you want to clone and choose 'Clone to Brands'.
Select the brand(s) you want the email to be cloned to and press the 'Clone' button.
You will now have an email in the desired brand.
Need more help? Contact support via live chat within Knak using the chat bubble in the bottom right corner or email email@example.com