Fashionable fragrance, fundamentally (2,7)

I believe the answer is:

in essence

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'fundamentally' is the definition.
(synonyms)

'fashionable fragrance' is the wordplay.
'fashionable' becomes 'in' (in can mean fashionable or trendy).
'fragrance' becomes 'essence' (I can't justify this - if you can you should give a lot more credence to this answer).
'in'+'essence'='IN ESSENCE'

Can you help me to learn more?

(Other definitions for in essence that I've seen before include "Basically" , "at bottom" , "Substantially" , "Fundamentally" .)

I've seen this clue in the Financial Times.

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