Legend about fencing clubs' striking effect (5)
I believe the answer is:
eclat
'striking effect' is the definition.
(I've seen this before)
'legend about fencing clubs'' is the wordplay.
'legend' becomes 'tale' (I've seen this in other clues).
'about' says the letters should be written in reverse.
'fencing' is an insertion indicator (to fence can mean to contain or put a limit round).
'clubs'' becomes 'c' (abbreviation used in card games such as bridge).
'tale' written backwards gives 'elat'.
'elat' enclosing 'c' is 'ECLAT'.
(Other definitions for eclat that I've seen before include "Showy effect (Fr.)" , "Universal approval" , "Fame -- style" , "Splash" , "Acclaim; showy display" .)