In a super over, can a bowler who did not bowl during the match bowl? or only those bowlers who bowled during the match are allowed to bowl super over?
As long as they are part of the playing XI (including any made concussion substitutes), they should be able to bowl, as there does not appear to be any rules stating against this.
From the ICC T20I Playing Conditions*:
Only nominated players in the match (including activated concussion replacements) may participate in the Super Over. Should any player (including the batsmen and bowler) be unable to continue to participate in the Super Over due to injury, illness or other wholly acceptable reasons, the relevant Playing Conditions as they apply in the match shall also apply in the Super Over.
Besides, the fielding team are highly likely to pick their best bowler for the Super Over, so in all likelyhood, they would have already bowled...
* It appears that the ICC have only updated the T20I Playing Conditions documents with the new Super Over rules, though I would imagine that the same Super Over rules will also apply to ODIs too.