The CD version lets you make an entry name it stores lots of info like your score averages, handicap, grand slam wins, etc.
Well, I can't build any sort of name entry system, but I can tell you where to go to just edit the entries in a hex editor if you ever wanted to add a custom name for your scorecard.
8 letter names are an easy substitution with a hex editor. Player 1 name begins at $838F2 and Player 2 name begins at $838FB. Bytes $838FA and $83903 are FE and the game reads it to know that the name is over.
Up to 12 digit custom names fit nicely but require a small change to the addressing.
$83AA0 change from FB to FF, this tells the game the new start point for the Player 2 name.
Player 1 name begins at $838F2
Player 1 name ends at $838FD
Byte $838FE must be FE to end name
Player 2 name begins at $838FF
Player 2 name ends at $8390A
Byte $8390B must be FE to end name
I'm assuming someone could build some sort of tool that could generate a patch file for you based on text you input. I'm not that person, you'll have to do it manually. Remember that Neo Geo games are byte swapped (big endianness or whatever). Don't forget to backup your file first.