nba live 08 and 09 sliders

if we play online and invite a friend to play (PS3), does the modification that we made on the sliders will take effect also online? or sliders is by default in online gaming?

No, your personal sliders are not used in either game when you play online.

thanks. good to know we have only one settings to use during online game. i thought the settings will be based on the user settings who does the invitation.

No, just the standard online sliders. That has its drawbacks of course but it does level the playing field in a way.