Doe de test

using System;
using System.Linq;
using System.Text;
public class Program
{
    public static void Main()
    {
     const string cHash = "4A52205A4E5852204C42484520464253474A4E4552";
     System.Console.WriteLine($"{RetrieveSolution(cHash)}");
     }
     private static string RetrieveSolution(string hash)
     {
         byte[] raw = new byte[hash.Length / 2];
         for (int i = 0; i < raw.Length; i++)
         {
               raw[i] = Convert.ToByte(hash.Substring(i * 2, 2), 16);
         }
         hash = Encoding.ASCII.GetString(raw);
         return !string.IsNullOrEmpty(hash)
              ? new string(hash.Select(x => (x >= 'a' && x <= 'z')
                  ? (char)((x - 'a' + 13) % 26 + 'a') : ((x >= 'A' && x <= 'Z')
                  ? (char)((x - 'A' + 13) % 26 + 'A') : x)).ToArray())
              : hash;
     }
}