Can the MoCA 2.5 adapters be connected using Eero 6?

To answer this question, we need to know what you mean by connected using Eero 6. If you mean connecting the ECB to Eero 6, then to your device to extend your wired network, this is not the recommended configuration and is not supported by our support team. If you mean connecting the Eero 6 to an ECB that is connected to a coax connection coming out of the wall, then yes, this should work.