Its possible to send the User a login 2FA code via E-Mail?
There is no such built-in functionality in CS-Cart. I think this add-on may be your best bet:
It works via Google Authenticator, not e-mail, but still provides an additional layer of security.
thank you for your answer.
I have found now this addon which is also interesting
Hello. This addon allows to confirm email during registration. Feel free to ask any question.