The 6th gen is the 128-bit era, this is the time of the ps2, xbox, game cube and sega dreamcast, there was apperintly another console called the XaviXPort but i never heard of it. This era ended arounf 2005 when the xbox 360 came out.
Onimusha Dawn of Dreams
This is the fourth of the series.
The game set few years after the third installment with new character.
Personally i think this is mostly RPG-based with switching party system.
And some new character. Btw, do you know where is "Samanosuke Akechi" ?
Best Onimusha game i ever played