Can you recognize accents in songs?

I would say mostly not! Sometimes it's possible to figure it out at words such as 'can't'. If it tends to be an [a:] sound which would imply that it is rather british or an [ae] sound which would make it american. However you can never be sure if the band did not put on a fake accent which differs from their origin in order to adapt to the 'song's origin'.

It is sometimes easy to discertain different dialects during song. If a singer from say, Ireland, was to attempt an American song, he would surely sound at least a bit different. No matter how hard an English speaker tries, it is very difficult to impersonate a different dialect of the same language...it takes much time being around people who speak it to attain that certain dialect.