Disclaimer

This answer assumes ( as I can not discern any such details from the question ) that you already have your applications communicating, and are able to serialize and deserialize JSON and what you desire assistance with is the automatic sending of data on object update.

Use encapsulation to handle updates

By using c#'s class mechanisms, you can - make sure your "Sales" variable is only updated via your publicly displayed update method - the publicly displayed update method also sends the new data to your other application

class SalesContainer
{
    private string _sales;

    public string getSales()
    {
        return _sales;
    }

    public string updateSales (string sales)
    {
        _sales = sales;
        sendData(sales);
    }

    private sendData(string json)
    {
        // your sending logic here
    }
}

Alternatively, you can look a bit into operator overload to allow you to makes less changes on your existing codebase.

I understand you have two applications. They cann't communicate with each other directly. You need a third-party mediation. A file, database, network stream, or MemoryMappedFile. QlikSense.NET application push update to mediation, and Bot Framework application read the update from mediation.

I think this is cross-process communication problemn, so each cross-process communication solution is feasible.