Ok, so I did some more testing and...
1. Language doesn't matter it still crashes on me on route 1.
2. Clean install of Shield and deletion of tickets beforehand doesn't matter, still crashes.
3. I tried another similar mod from Game Banana and it worked. Apparently that creator had trouble with a route in Shield as well (route 3). Maybe something similar is happening for route 1.
Oddly enough and thankfully, it's flawless on Sword. Got a team of starters set up thanks to you! If by any chance you can take a look into route 1 on Shield, I'd greatly appreciate it. If not, no worries. I'm kind of interested in learning how to do this so I'll stick with Sword until I can learn how to edit tables on my end and maybe fix this little bug. Thanks again for your hard work!
So i have no idea what caused it or how ive manage to fixed it. I download the file i posted here and restarted my shield game and indeed i crashed after the slumber weald part of the story, though it wasnt right away so that lead me to think it was something with the "personal_total.bin" file.
1. deleted "Personal_total.bin", still crash though at a different point this time. So it could be something wrong with one of the spawn.
2. Noticed that my total spawn chance for route 1 overworld in shield is only 95% whereas my sword is 100%. I changed that to match sword but still crashed.
3. removed all overworld spawn and it didnt crash anymore so i started to add each spawn back 1 by 1 to see which one of them caused the crash.
4. Got all the way to the last pokemon and still didnt crash anymore.
Long story short... the file is seem to be fixed and is exactly how i have it at step 2, even though it crashed at step 2 before. I've ran around route 1 for about 30mins to get all the pokemon that could spawn to spawn and they all spawned fine, even the rare spawn ones.