HTTP 301 redirection with Kong Ingress

Using:
Kong Ingress 2.0.5
EKS cluster

Is there a way to simple, 301 redirections just with an Ingress/KongIngress/KongPlugin configuration?

My use-case is:
user enters www.foo.com, has to be redirected to app.bar.com with a 301 Redirect.

I’ve already tried request-transformer and request-termination like this:

apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: dev-redirect-transformer
config: 
  add:
    headers:
    - "Location: https://app.bar.com"
    - "demo: injected-by-kong"
plugin: request-transformer
enabled: true
---
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: dev-redirect-termination
config: 
  status_code: 301
  message: "test"
plugin: request-termination
enabled: true

And serverless like this:

apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: dev-redirect-post
config: 
  header_filter: kong.response.exit(301, 'page moved - redirecting...', {['Location'] = 'https://app.bar.com/' .. kong.request.get_path_with_query():gsub("%/test1/", "/test2/")})
plugin: post-function

with this Ingress configuration:

kind: Ingress
apiVersion: extensions/v1beta1
metadata:
  name: dev-other-ingress-test
  namespace: redirect-test
  annotations:
    konghq.com/plugins: "dev-redirect-post"
or
    konghq.com/plugins: "dev-redirect-transformer"
    konghq.com/plugins: "dev-redirect-termination"
spec:
  rules:
    - host: www.foo.com
  tls:
  - hosts:
    - www.foo.com
    secretName: foo-ssl

To no avail.

Am I doing something/wrong, is this even possible just with Kong?
Any help is appreciated, thanks.