How to use JSON input in Kibana

Hi, I want to add a field in my JSON query for a field in KIbana like this:

    "load_time_outlier": {
      "percentiles": {
        "field": "load_time",
        "tdigest": {
          "execution_hint": "high_accuracy"    
        }
      }

How can I add this to my Kibana Lens/Dashboard, I can see that in the older versions of Kibana there was a Input JSON field, where we can add a custom JSON parameters, how can I make my query custom by adding the execution_hint parameter?