Edit shiny charm in bw2

[Didus]

I'm currently trying to improve the shiny charm in pokemon white 2.

Why do I try to do that rather than edit the overall shiny odd ? It's because in pokemon volt white 2 drayano made some cleanup in the game files and it's impossible to reinsert arm9.bin back to the game once it's edited.

Following what @Andibad and @Bond697 said in the topics above, I tried to find a way to edit shiny charm but i'm stuck.

I don't know what value I should edit since it's a key item. Does it work the same as berries ?

[Bond697]

Do you just want to change how many extra tries at a shiny the Shiny Charm gives you?  Why can't you edit the ARM9 and put it back?  You're not making it any bigger, right?

[Didus]

I can edit the arm9 but I can't insert it back to the game since in drayano's volt white 2, arm9 is different from the original one.
If i try to insert an edited arm9 back to the game with crystaltile2, i'll be stuck in an infinite loop telling me to insert it back in another offset.
I tried to insert it back with tinke too be the game crashes at launch.

If you have a solution for arm9 you'll be my savior

Edit : When i edit arm9 it works fine with official pokemon white 2 us
With volt white 2 when i uncompress the arm9 to edit the right offset, the size changes and I can't compress it back to its original size.
 

Edited October 15, 2020 by Didus
additionnal info