It’s essential to share national sporting venue (5)
I believe the answer is:
arena
'sporting venue' is the definition.
(sports arena)
'it's essential to share national' is the wordplay.
'it's essential to' indicates a hidden word (I've seen this in other clues).
'ARENA' can be found hidden inside 'share national'.
(Other definitions for arena that I've seen before include "park" , "Where one may find sportsmen" , "Coliseum" , "place for sporting contest" , "Scene of combat" .)