Setter's distinct identity is me, personally (6)
I believe the answer is:
myself
'me personally' is the definition.
(I've seen this before)
'setter's distinct identity' is the wordplay.
'setter's' becomes 'my' (belonging to the crossword setter).
'distinct identity' becomes 'self' (I've seen this before. I am not sure about the 'distinct' bit.).
'my'+'self'='MYSELF'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for myself that I've seen before include "I personally" , "Crossword compiler" , "Me, in person" , "Reflexive pronoun" , "Emphatically, me" .)