Is it possible to multi chip synch. single ORX channels of multiple ADRV9009 devices in ADC stitching mode with 450 MHz bandwidth?
Multichip sync basically synchronize the LO frequency with reference and same LO goes to ORx path. So theoretically stitching is done in digital domain and they should maintain phase sync.
Please test same on evaluation board to see if the performance is same as what you are expecting.