Not sure everybody is aware of that so ill share what i found out ...
Working on my roster which makes me double or tripple a few players to place them in different teams, i first started creating players and assigning the iff...
but since i hear there is a CAP limit 60 or 80 dont remember, i experimented with changing exiting players to the name i wanted then assign proper iff
As some of you who tried might have noticed : there can be some bugs if u dont respect a certain rule:
1) the Last and the First Name of the players must have the same number of letters. ex : Joe Chasan can be renamed to Ron Artest
2) i found this one the hard way : select a Last Name (and First name too i think but im not sure any more) that is only once in the roster cuz if u rename Jackie butler to Jordan for example, Caron's new last name will also be Jordan...
I know it aint the perfect solution... but it definatly helped me...
so make sure your target is the only one with this last name, and make sure he is in free agents or on a team where trades can be done ex : Joe Chasan was in the 2K celibrity team , so no use using him:)
To easily spot which players are not available for trade you can use the Excel file that was done on page 3 in that thread : viewtopic.php?f=94&t=64237
hope this helps a few others