How to serve multiple dashboard from multiple traefik using one administrative-traefik

TLDR: How to serve dashboards from multiple ingress-controllers (traefiks) using single Ingress-controller dedicated to serve these dashboards? And I read Docs

With traefik 1.7 I have multiple ingress controllers deployed in the "kube-system" namespace. Each is for different purposes - mainly monitoring its own subset of namespaces.
There is one main Traefik in the kube-system namespace, which is serving only "internal" cluster, administrative ingress objects. dashboards, grafanas, etc.
Every other traefik-dashboard is exposed by own Ingress object which is then intercepted by that administrative-traefik. So each dashboard has own URL: traefik-x.example.com traefik-y.example.com.

How to achieve same with traefik v2? Using secure setup?

What are the best or "all possible" ways to access dashboard in traefik v2?

  1. Port forwarding suggested here https://github.com/containous/traefik-helm-chart/issues/85#issuecomment-598347705 doesn't work without IngressRoute. Is that intentional and how that works?
  2. I was trying to expose using NodePort only and it didn't work without IngressRoute definition. kubectl-proxy didn't work too.
  3. I was able to expose Dashboard using default web entrypoint and it did work.
    But "service" points to some api@internal TraefikService. here is my IngressRouter
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: admin-ing-dashboard
  labels:
    app: traefik
    release: admin-ing
spec:
  entryPoints:
  - web
  # - traefik
  routes:
  - match: Host(`admin-ing.test`)
    kind: Rule
    services:
    # - name: admin-ing-dashboard
    #   port: 9000
    - name: api@internal
      kind: TraefikService

But some other traefik will be pointing to the same api@internal. How to make traefik understand that I'm requesting dashboard of some other traefik deployment?
For example next I want to setup default-ing traefik which will be serving public apps in default namespace.
Again. I have tried to create individual service admin-ing-dashboard for exposing dashboard only. But it didn't work.

Installing traefik2 using official chart
Is that possible at all? How to view the other traefik dashboards on the same cluster and namespace?

Have you found a solution ?