City formerly no good in Ireland transformed (9)
I believe the answer is:
leningrad
'city' is the definition.
(Leningrad is an example)
'no good in ireland transformed' is the wordplay.
'no good' becomes 'ng' (abbreviation).
'in' means one lot of letters goes inside another.
'transformed' is an anagram indicator.
'ireland' anagrammed gives 'lenirad'.
'ng' put inside 'lenirad' is 'LENINGRAD'.
'formerly' acts as a link.
This may not be right. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for leningrad that I've seen before include "Former name of city" , "old city" , "St Petersburg, 1924-91" , "Name of St Petersburg from 1924 to 1991" , "Soviet period name for St Petersburg" .)