If you hadn't seen already, a few days ago, I discovered a graphic that suggested a debug mode existed in MMSF3.
Here are the contents of the sprite file that hinted at this.
A Debug mode would be interesting but the game has no debug scripts unlike the previous Star Force games or BN games. I passed this on to Prof.9 after I couldn't access the option through basic cursor hacking. The graphic cannot be accessed. After he looked at it, he could not find the debug mode. However, he created a hack that makes the game start in the debug room. When selecting New Game, instead of beginning with the cutscene on the roof, you'll start in the room called Debug. Here, surprisingly, are people which only appear when you start a new game. These are obviously placed there for the sole purpose of testing overworld object tricks. The Debug room takes the appearence of the candy shop and the text of Echo Ridge. The NPC text is taken from a small file which only the debug room uses. It is likely that this small file would have contained the debug scripts all the other games had. There's isn't much left in the debug room except some simulations. Maybe there are more but this is a close enough answer to the debug option in the sprite file.
I recorded a video showing the test subjects in the debug room.
Two Action Replay cheats were made from trying to hack the debug mode.
I made the quick start code.
Quick Start (Red Joker)
This cheat skips the Capcom screen and the ESRB note which cannot be skipped any other way, even by soft resetting.
Access Debug Room (Red Joker)
Prof.9 made this code. From the title screen, selecting New Game will start a new game in the Debug room. There, you can explore the debug room like in the video.
And one more thing. I didn't reach the wave road in the video but I checked and there are no viruses, the exit freezes the game like the ground exit does. Also, even though the ACCESS panel can't be seen, there is an access point at the end of the road. However, it also freezes the game.
Huge thanks to Prof.9 for looking into this. I've always wanted to explore the debug mode of a game. Even though it wasn't what I expected, it was fun. MMSF2 has a similar option as well. There is an unused Japanese option in the title screen that reads "Documentation Plaza". I wonder what's up with that?