The problem is that I can't think of any PPG members that were big enough before Wuxing's expansion and jump up to have given the Japanese Mega's a run for their money, although I suppose Wuxing could be argued even though their roots seems a little jumbled in the early books. I'd be much more likely to expect someone like the PacRim Bank to - hostilely - take over the actual HSBC Bank from the central HSBC Holding company, with the other half gobbled up by people like the Swiss Bank Corporation or HKB since they apparently hoovered up a lot of the UK's and Europe's financial concerns when going double A rated.
That's assuming of course they get split up or taken over by someone else. As one of the largest banking groups in the world they'd be a pretty hard target to take over or try and dismember. *Shrug* Either way I guess.