not a good advice
you will have some problem. first of all you also need to copy the appearence.dbf
but if you copy these files in your roster and then try to make a dysnaty, the game will crash (it did for me)
the best way is to use a dbf editor (DB commander) and copy the lines from your dynasty roster to your current roster (hope it is clear)
I did so and it is just perfect !!