No. In statements of identity ("X is Y" or "Y is X"), both the nouns X and Y are in the nominative.
That is true also in English and many other languages in addition to Hungarian.
(True, nowadays English says "It's me" instead of "It is I", but historically it was the second form that was used. And it can be argued that the "me" in "it's me" is not accusative but rather an emphatic form of the nominative "I", like the "moi" in French "c'est moi".)