Searching a way for Animate to automatically replace each images with other ones

No problem if you don't have Illustrator.

As suggested by Chen, you can try some importing approach and hopefully your images will be replaced.

Alternatively, here is a small script to replace bitmaps from a imported PSD file.

Preview:

Usage/considerations:

- Select the folder that directly contains the imported bitmaps and run the script;

- Photoshop appends numerical indexes to layers with the same names using dashes while Animate CC uses underscores. So if one outputs to "image-1", "image-2", the other outputs "image_1", "image_2". So, for these cases, the images won't be replaced.

Swap External Images JSFL script download:

Swap External Bitmaps.jsfl - Google Drive

JSFL code for reference only. Feel free to fix and/or optimize if needed:

var uri;
function importImages()
{
     var doc = fl.getDocumentDOM();
     var lib;
     var libFolder;
     if (!doc)
          return;
     lib = doc.library;
     libFolder = lib.getSelectedItems()[0].name;
     if (!libFolder)
          return;
     try
     {
          var externalBitmaps = getExternalBitmaps();
          var path;
          var newName;
          if (!externalBitmaps)
               return;
          for (var i = 0, total = externalBitmaps.length; i < total; i++)
          {
               var path = uri + "/" + externalBitmaps;
               var newName = externalBitmaps.replace(".png", "");
               doc.importFile(path, true, false, false);
               lib.selectItem(externalBitmaps);
               lib.renameItem(newName);
               lib.moveToFolder(libFolder, newName, true);
          }
     }
     catch(error)
     {
          fl.trace(externalBitmaps);
          fl.trace(error);
          fl.trace("___________");
     }
}
function getExternalBitmaps()
{
     uri = fl.browseForFolderURL("select", "Select the folder containing the PNGs.");
     return FLfile.listFolder(uri + "/*.png", "Images.");
}
importImages();

I hope this helps.

Regards,

JC