* Time starts once Disc 1 is booted
* Boot Disc 1, skip splash cutscenes
* Press Options, set Scene Skip on
* Enter these values into Field Sub Menu:
   Map Group: 01
   Map Number: 1504
   Map SubNumber: 01
  But do NOT activate them
* Press Start Game
* Immediately activate Field Sub Menu values
* Skip cutscene
* Save game

* Boot Disc 2
* Press Continue
* Enter these values into Field Sub Menu:
   Debug Mode: ON
   Map Number: 6977
  But do NOT activate them
* Load the saved game
* Skip the cutscene
* Wait for the game to load in (Map Number = 4200)
* Activate Field Sub Menu value
   (Do the rest VERY QUICKLY! Or else you will die.)
* Close Debug Menu, then open Battle Debug Menu
* Navigate to Debug / Battle / Char / Param
* Set Char No. to 4
* Set HP to a negative value as quickly as possible
* Skip 2 cutscenes
* Time ends once Grandia logo appears

To access debug mode:
https://grandia.wikia.com/wiki/User_blog:Liam48D/To_access_Grandia_III%27s_debug_mode...

TL;DR You will need to use a cheat code and to have access to a second controller;
as such, playing on an emulator (as described in the blog post) is highly recommended.