Poem, after he translated, that is powerful piece by European (3,6,6)

I believe the answer is:

the faerie queene

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'poem' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'after he translated that is powerful piece by european' is the wordplay.
'translated' is an anagram indicator.
'that is' becomes 'ie' (abbreviation for id est, 'that is' in Latin).
'powerful piece' becomes 'queen' (I've seen this in another clue).
'by' is a charade indicator (letters next to each other).
'european' becomes 'e' (abbreviation e.g. EU).
'after'+'he'='afterhe'
'afterhe' with letters rearranged gives 'thefaer'.
'thefaer'+'ie'+'queen'+'e'='THE FAERIE QUEENE'

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I've seen this clue in The Telegraph.

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