Unity Editor script. Select multiple texture files for one material in Project window, then click Tools -> Create Materials For Textures. A new material will be created. Adjust Smoothness and other settings to match expected render.

CreateMaterialsForTextures.cs

using UnityEngine;
using UnityEditor;
using System.Linq;

// Original source: http://answers.unity.com/answers/746039/view.html

public class CreateMaterialsForTextures : ScriptableWizard
{
    [MenuItem("Tools/CreateMaterialsForTextures")]
    static void CreateMaterials()
    {
        int selectedTextures = 0;
        try
        {
            AssetDatabase.StartAssetEditing();
            var textures = Selection.GetFiltered(typeof(Texture), SelectionMode.Assets).Cast<Texture>();



            foreach (var tex in textures)
            {
                selectedTextures++;
                string texturePath = AssetDatabase.GetAssetPath(tex);
                string assetFolderPath = texturePath.Substring(0, texturePath.LastIndexOf("/"));
                string textureFileName = texturePath.Substring(texturePath.LastIndexOf("/")).ToLower();
                string materialFilePath = assetFolderPath + "/NewMaterial.mat";

                Material mat;
                if (AssetDatabase.LoadAssetAtPath(materialFilePath, typeof(Material)) != null)
                {
                    mat = (Material)AssetDatabase.LoadAssetAtPath(materialFilePath, typeof(Material));
                } else
                {
                    mat = new Material(Shader.Find("Standard"));
                }
                if(textureFileName.Contains("diffuse") || textureFileName.Contains("albedo") )
                {
                    mat.mainTexture = tex;
                }
                else if (textureFileName.Contains("normal"))
                {
                    mat.SetTexture("_BumpMap", tex);
                    mat.EnableKeyword("_NORMALMAP");
                }
                else if (textureFileName.Contains("height"))
                {
                    mat.SetTexture("_ParallaxMap", tex);
                    mat.EnableKeyword("_PARALLAXMAP");
                }
                else if(textureFileName.Contains("metallic") || (textureFileName.Contains("glossiness")))
                {
                    mat.SetTexture("_MetallicGlossMap", tex);
                    mat.EnableKeyword("_METALLICGLOSSMAP");
                }
                else if (textureFileName.Contains("occlusion") || textureFileName.Contains("ambient") || textureFileName.Contains("_ao") || textureFileName.Contains(" ao"))
                {
                    mat.SetTexture("_OcclusionMap", tex);
                }
                else if (textureFileName.Contains("reflection") || textureFileName.Contains("specular"))
                {
                    mat.SetTexture("_SpecGlossMap", tex);
                    mat.EnableKeyword("_SPECGLOSSMAP");
                }

                if (AssetDatabase.LoadAssetAtPath(materialFilePath, typeof(Material)) == null)
                {
                    AssetDatabase.CreateAsset(mat, materialFilePath);
                }
            }
        }
        finally
        {
            AssetDatabase.StopAssetEditing();
            AssetDatabase.SaveAssets();
            if(selectedTextures==0)
            {
                Debug.LogError("No textures were selected. Material not created.");
            }
        }
    }
}