To Meloni, the Left say: “Reformation of Italy is wrong” (10)
I believe the answer is:
illegality
'is wrong' is the definition.
(thesaurus)
'to meloni the left say reformation of italy' is the wordplay.
'to meloni' becomes 'il' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'the left say' becomes 'leg' (left leg).
'reformation of' indicates an anagram (I've seen 'reformation' mean this).
'italy' with letters rearranged gives 'ality'.
'il'+'leg'+'ality'='ILLEGALITY'
Can you help me to learn more?
(Another definition for illegality that I've seen is " law-breaking".)