320 Service will feed two 200 amp subpanels (they will each have 160 amps each). Can each subpanel be feed with a 2/0-2/0-2/0-1 copper wire or would you recommend something else? Subpanels will be wired to a 22kW generator with smart switch and load shedding. Thanks.

That's what I would use. That or 4/0AL.