TranslatorChecker.cs

using System;
using System.Collections.Generic;
using System.IO;

class Program
{
    static void Main(string[] args)
    {
        if (args.Length == 0)
        {
            return;
        }
        var source = args[0];
        var mds = Directory.GetFiles(source, "*.md", SearchOption.AllDirectories);
        var dict = new Dictionary<string, int>();
        foreach (var md in mds)
        {
            var type = FindTranslationType(md);
            int count;
            if (!dict.TryGetValue(type, out count))
            {
                count = 0;
            }
            dict[type] = ++count;
        }
        foreach (var pair in dict)
        {
            Console.WriteLine($"type={pair.Key}, count={pair.Value}");
        }
    }

    static string FindTranslationType(string md)
    {
        const string translationHeader = "ms.translationtype: ";
        using (var reader = File.OpenText(md))
        {
            string line;
            while ((line = reader.ReadLine()) != null)
            {
                if (line.StartsWith(translationHeader))
                {
                    return line.Substring(translationHeader.Length);
                }
            }
        }
        Console.WriteLine(md);
        return "N/A";
    }
}