OK, need to explain what's going on here.
The player and team data are each grouped by team. This area is limited due to ROM size constraints. When the ROM was made, obviously the ROM was not meant to be modified, so there is a fixed size for player and team data.
Each player/team data group is referenced by a list of pointers. So in this list of pointers, ANH data is at one spot, BOS is at another spot, etc. This table is used by the ROM to grab the data.
In Genesis, the NOSE editor gets around the size limitation by moving some of this player/team data to an empty spot in the ROM. For example, we can move the data for ANH and BOS, and change the pointer list to point at the new spots. This frees up the space originally taken by ANH and BOS and that space can be used to expand the other team rosters (Now instead of fitting 28 teams in that spot, we have 26 teams used to fill it).
When I originally made this tool, it was able to do this, move the team data out, to allow expansion of the teams. Unfortunately, this broke compatibility with Statto's SNES Editor. For some reason, his editor doesn't look at the pointer list; the data positions are hard coded into it.
So, since Statto's SNES Editor is limited, and my plan was to use this as an assistant to it, I had to change it so that it worked with the editor.
There is a way to make this work. Though you will have to copy and paste some stuff in a hex editor, and break compatibility with the SNES editor.
EDIT: So, my previous response to your original question should have been "It could work, with some caveats..."
The best way to work around it would be to just use first initials instead of whole names. This would gain you some space on each team. Don't include a period, just the first initial.