Riposte requires right sword fencing skill (8)
I believe the answer is:
repartee
'riposte' is the definition.
(thesaurus)
'right sword fencing skill' is the wordplay.
'right' becomes 'r' (common abbreviation).
'sword' becomes 'epee' (epee is a kind of sword).
'fencing' is an insertion indicator (to fence can mean to contain or put a limit round).
'skill' becomes 'art' (I've seen this before).
'epee' going around 'art' is 'epartee'.
'r'+'epartee'='REPARTEE'
'requires' acts as a link.
(Other definitions for repartee that I've seen before include "Smart retorts or witty replies" , "Clever or witty rejoinder" , "Comic dialogue" , "Lively exchange" , "Series of clever replies" .)