Board Thread:Naruto Discussions/@comment-36755597-20180829215104/@comment-3279282-20180830185936

What? Kekkei Tota is a combination of three natures, not two kekkei genkai. If it's hereditary or not is unknown, because teaching someone doesn't mean that they don't have the kekkei genkai for it (see Rasa).

A Kekkei Tota Sharingan can't exist because a Sharingan isn't an elemental kekkei genkai.