if you're talking about copying teams, you can with the "teams" link on the left margin. the kicker is, you can't do it to all the insert sets with that set year because it matches card numbers to the players. and you have to careful sometimes because some sets may have a player on a specific current team and another insert set with that same player on a past team.
the good part is too, if you edit the CL and select teams, you can just copy and paste the same team in all the fields for that insert set.