byte_array_hex.cs

using System;
using System.Linq;

var bytes = new byte[] { /* ... */ };

var hex = new string(bytes.SelectMany(x => x.ToString("x2").ToCharArray()).ToArray());

var data = Enumerable.Range(0, hex.Length).Where(x => x % 2 == 0)
                                          .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                                          .ToArray();