Script fields in nested query

Elastic Stack Elasticsearch
1

Is there a way to run a "script_fields" adding fields to the returned inner_hits? Example:

{
   "nested": {
      "inner_hits": {},
      "path": "companies",
      "score_mode": "sum",
      "query": {},
      "script_fields": {
         "overlap" : {
            "script": {
               "source": "................................",
               "params": {
                   "from": "2012-01-01",
                    "to": "2015-06-30"
                }
            }
         }                
      }         
}

I execute n nested queries passing to each one a set of specific params. The idea is having the source script to assign a value to the overlap field for each one of the inner hits based on the provided params.

2

Any suggestion?