envoy-2.yaml

static_resources:
  listeners:
  - name: listener_0
    address:
      socket_address:
        address: 0.0.0.0
        port_value: 10000    
    filter_chains:
    - filters:
      - name: envoy.filters.network.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
          stat_prefix: edge
          http_filters:
          - name: envoy.filters.http.router
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router
          route_config:
            virtual_hosts:
            - name: direct_response_service
              domains: ["*"]
              routes:
              - match:
                  prefix: "/"
                direct_response:
                  status: 200
                  body:
                    inline_string: "Hello"

Line 15 is missing the type.
Add right below:

           typed_config:
             "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router

Thanks @eduardocolombo-bnet -- fixed!