Yepp, but like we discussed in those PMs the In-Game-Core is another issue entirely.
Now to think about it... it may be interesting to implement that (Multi USB device support).
USB hub support should already be present inside OPL, if uLE could already use hubs (Unlinke PS2ESDL, OPL doesn't use stripped-down/crippled USB drivers).
True, the Hub-Implementation seems to be standartized, but I hope someone with more knowledge about it can chime in and answer our questions. :)
From my understanding of how the USB topology was designed... USB hosts/devices also have a hub inside them (In other words, USB hub support is required to be present in any USB controller driver).
Maybe someone else who perfectly understands the USB 1.1 specification can give a much clearer, correct and better answer though.