MongoDB Wildcard Indexes - How to cover the projection with the index

Working with Data
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1

I have a dynamic schema on mongodb for different workflow templates. Each workflow template has data attributes associated which is stored as normal <key,value>
{
_id : “1”
data : {
team_id : “ABC”,
template_id : “retail_sales”,
recorded_at : “”,
billing_state : “KA”,
pin_code : “50001”
}
}

{
  _id : 2
  data : {
    team_id : "ABC",
    template_id : "simple_crm",
    recorded_at : "",
    status : "NEW",
    loan_amount : 10000
  }
}

I understand that with 4.2 there is a wildcard index which I wanted to use for aggregate queries. The have created a full document wildcard index as below
{
“$data.**” : 1
}

On executing the query I can see that the index is used.
db.getCollection(“view_status_dashboard”).aggregate(
[
{
“$match” : {
“data.team_id” : “ABC”,
“data.template_id” : “retail_sales”
}
}
},

    {
        $project : {
            _id : 0,
            data: 1
        }
    }
])

However the projection is making a “FETCH” call which increases the memory.
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