Redirect the outbound access through Virtual Service to external proxy

Networking
1

Target want to route the outbound traffic from mesh sidecar to egressgateway and then redirect the traffic to external proxy. I have edited the virtual service as below, seem the destination cannot be input the IP and is there any other way to do that ?

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: direct-cnn-through-egress-gateway
  namespace: demo-test-1
spec:
  hosts:
  - edition.cnn.com
  gateways:
  - istio-egressgateway.istio-system.svc.cluster.local
  - mesh
  http:
  - match:
    - gateways:
      - mesh
      port: 80
    route:
    - destination:
        host: istio-egressgateway.istio-system.svc.cluster.local
        port:
          number: 80
      weight: 100
  - match:
    - gateways:
      - istio-egressgateway.istio-system.svc.cluster.local
      port: 80
    route:
    - destination:
        host: [PROXY_IP]
        port:
          number: 3128
      weight: 100