Keen to be seen in ABBA video (4)
I believe the answer is:
avid
'keen' is the definition.
(I've seen this before)
'seen in abba video' is the wordplay.
'seen in' indicates the answer is hidden within the clue.
'AVID' is hidden in the letters of 'abba video'.
'to be' is the link.
(Other definitions for avid that I've seen before include "Greedy like diva" , "hungry" , "'Eager, enthusiastic (4)'" , "Keen or greedy" , "Burning" .)