Due to the limited features of the Essentials Edition, I'm afraid that you will have to update/patch the hosts interactively. Even Update Manager might not be very helpful, because Essentials doesn't support DRS/vMotion, and there must not be any powered on VMs on the host to remediate. You will also need to find a workaround for the ESXi host on which vCenter Server is running, except the vCenter Server instances for each Kit are running on another Kit's hosts.
André