Follow the steps to open a franchise file, as documented in Xans MRE
When your file is opened, a .db file is generated. THAT is how you access the raw data tables. Simply open that file with the DB Editor.
You MUST leave the franchise file open to make changes. If you save and exit the file in the roster editor, you lose the ability to access the tables.
Use the DB Editor to export table to .csv, make your changes, import. Save.
You can edit the data IN the editor, but this is monotonous unless you are only editing a few fields. Its MUCH easier to mass edit via .csv
If you are using a retro roster, this means you can edit the following for realism;
Player stats, career stats
Coach W-L records
Team W-L records
Expansion cities, city info
Training Staff names/attributes
Salary cap info (maximum)
Max contract info (maximum, RFA values)
Draft order
I suggest using MDB19 v2.2 Editor which can be found on Football Idiot, it has a usability feature regarding the table fields which is simply invaluable.
The tables haven't changed since the PS2 era, aside from some additions. If encryption can be broken, there is no reason we shouldn't be able to edit PS4/X1 rosters.. and PS5/X? as well...
**This was tested with M12 franchise only**

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