Automatize the reimportation of working file from a folder ended with '~' (a demo video is available here https://youtu.be/S-yyK3Fzw3c)

ReimportAsset.cs

using UnityEngine;
using UnityEditor;
using System.Text.RegularExpressions;
using System.IO;

public class ReimportAsset : MonoBehaviour
{
    #region MenuItem Methods

    [MenuItem("Assets/Reimport from ~ &R", false, priority = 40)]
    public static void ReimportFromWorkFile()
    {
        if (Selection.activeObject == null)
            return;

        bool refresh = false;
        Regex regex = new Regex("Assets/([^/]*)(.*)");
        string dataPath = Application.dataPath.Replace("Assets", "");
        foreach (UnityEngine.Object iObject in Selection.objects)
        {
            string assetPath = dataPath + AssetDatabase.GetAssetPath(iObject);
            string assetPathWork = regex.Replace(assetPath, "Assets/" + "$1" + "~" + "$2");
            if (!File.Exists(assetPathWork))
                Debug.Log("File " + iObject.name + "can't be reimport, the work file doesn't exist :(");
            else
            {
                File.Copy(assetPathWork, assetPath, true);
                refresh = true;
            }
        }
        if(refresh)
            AssetDatabase.Refresh();
    }

    [MenuItem("Assets/Reimport from ~ &R", true, priority = 40)]
    public static bool ReimportFromWorkFileValidate()
    {
        if (Selection.activeObject == null)
            return false;
        return true;
    }

    #endregion
}