In the normal case, to link another email address to the Weblate account, users need to own the email address and click the verification link. However, I found an issue, that allows adding another email address without clicking on the verification link.
Create a new openSUSE ID. Pick up a new email. In this example, I choose
Of course, you don't need to verify the email address for this openSUSE ID.
Then backs to weblate.org, go to Your profile > Authentication
Add the above openSUSE account as a new association.
That all, go to Account tab
https://demo.weblate.org/accounts/profile/#account, you will see the new email in your account's email field.
Weblate should only accept the association from verified openSUSE ID.