Write poetry, very intense rubbish (9)

I believe the answer is:

sonnetise

'write poetry' is the definition.
(to sonnetise is to write a sonnet)

'very intense rubbish' is the wordplay.
'very' becomes 'so' (both can mean 'extremely').
'rubbish' is an anagram indicator (a poor quality or rubbish spelling of the letters).
'intense' with letters rearranged gives 'nnetise'.
'so'+'nnetise'='SONNETISE'

I've seen this clue in The Guardian.

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