I want the fields "name" + "e-mail" required for all; for users and guests.
In settings this is not possible.
The name and e-male of registered users is applied automatically by default. How more required can it be?
The settings for making name and e-mail fields are in
Settings -> Comment form -> Field "Name" -> Required for guests
Settings -> Comment form -> Field "E-mail" -> Required for guests
So I really can't understand how you can make a statement like that.