You can start by checking this:

http://pastebin.com/4bg3q6FL

That was compiled awhile ago and describes what each GARC contains.

Specifically, this might be what you are looking for:

Code:

a/1/6/0 - trainer mugshots

 

Oh. Well then it could be this:

a\0\3\3

But a lot of stuff are in darc containers. They don't have darc headers though so I don't think they are actually DARC archives.

Ok the DARC files do contain a darc header. Basically use a hex editor to chop off the beginning of the file (everything before the darc header) and then you can open it in EveryFileExplorer.

a/0/3/3 definitely contains the trainer names. I found one that had the Japanese name for Steven. (specifically the graphics used in the champion battle)

 

You could in theory reinject. Just copy the darc back into the original container where the darc header starts overwriting the original data. (the stuff before the darc header is the only part that doesn't change)

The only problem is all the trainer names I've found are in Japanese. I don't know where it stores the English ones.

 

Ahh I see. Kaphotics replied to that saying that it's in a multi-language GARC and currently GARCTool can't repack those.