How add Real Rookies?

How add Real Rookies (lamelo, wiseman. edward and more ) in late my career? w/ nba 2k1 tool?

Yes, find their CF IDs with looyh's nba2k21 tool on the default roster. Write these down. Edit the player(s) and export their DNA. In your career roster make a dummy player. Edit the dummy. Import the rookie DNA. Assign to the team you want. Save the roster after importing for all rookies.