This isn't mine, but it seems to have been kept under the radar over the years so I figure some would like to know. This is a collection of bugfixes for Suikoden II, addressing most of the pressing problems. Essentially, just about everything except for a retranslation is in here for most versions of the game (though some fixes are US only). Yes, including ports of the fixes originally made to the PAL versions.https://github.com/pyriell/gs2-bugfixes
I remember the same person made something similar for the first Suikoden that fixed only a few bugs (escape talismans, bribe, and a couple of the rune spells doing nothing I think), and it was dedicated to the 1.0 version of the US disc. If anyone should happen to know where on the internet it ended up, let me know!
EDIT: I about forgot, the patcher is pretty much one of a kind. The .bat file is how you start it up, but it runs perfectly fine under Wine. Also, don't be afraid if it's taking a long time with one operation because the music patching takes a load of time.