Couple hosting popular European afternoon show (7)
I believe the answer is:
matinee
'afternoon show' is the definition.
(I've seen this before)
'couple hosting popular european' is the wordplay.
'couple' becomes 'mate' (synonyms).
'hosting' is an insertion indicator (inserted letters are welcomed in or hosted).
'popular' becomes 'in' ('in' can mean trendy).
'european' becomes 'e' (abbreviation e.g. EU).
'mate' placed around 'in' is 'matine'.
'matine'+'e'='MATINEE'
(Other definitions for matinee that I've seen before include "Afternoon showing of play" , "Afternoon theatre" , "Performance held in the afternoon" , "sort of jacket" , "in which players may appear?" .)