Display data for the future in a card

Yes you are right.
The definition of the sensor:

- platform: rest
  resource_template: "https://api.awattar.at/v1/marketdata" # alle verfügbaren zukünftigen Daten
  name: awattar_full
  json_attributes:
    - data
  scan_interval: 10800 #jede 3. Stunde neue Daten holen
  value_template: "{{ (value_json.data[0]) }}"

As far as i know does tibber also provide data but not via rest api. Its a GraphQL subscription or a websocket subscription and you need an personal authentication token. I dont know how this works, maybe someone figured it out already, or you dig through the documentation of tibber and HA. My Code is also just a bunch of copy and paste, so i can not give deeper support on this topic.

But as a dirty workaround for testing purposes you can also use the awattar.de api. The price is the same, you just have to add Taxes and Netznutzungsgebühren depending on the area you live and depending on which price you want as I did it in my previous post with the taxes *1.20 :

using plotly, it is quite easy to show future prices, I’m using the Nordpool integration and you just have to add “time_offset: 24h” to the entity for which you want to show the future prices in your graph

entity: sensor.nordpool_mwh_be_eur_3_10_0
name: Belpex
time_offset: 24h