There are few Applications available to do this job, but none comes free (or I looked at the wrong places!). After a little more research, I’ve found that by creating Workflow in Automator could do this job much easily and quickly. Following instructions will help you with creating your own Workflow.

Aim: I wanted to create a workflow to get all Files Dropped into it, filter Images only and Rename them with given name.

Automator is located in your Application Folder

• Choose Workflow from Options
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• You will have a Working space on the right and options on the left
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• Choose Files & Folders
• From this List, Drag and Drop “Filter Finder items” into your Workspace on the Right
  • You don’t have to do this step and Skip directly to renaming option, unless you want to filter the kind of file types you are renaming. For me, I wanted to rename Only Image files. Following step will explain how to apply filter and choose only images for renaming.
• 

• Select kind is image to Filter-out images only
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• Drag and Drop “Rename Finder Items” into your Workspace right after the Filter Finder items. Automator will prompt to add a Copy Option to make a Backup before performing renaming action. If you would like to make a Copy of files before renaming them, you could Select Add from the prompt otherwise Select Don’t Add (I wanted to rename, So I selected Don’t Add).
• 
• Now your Workflow will look alike this
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• From the First Left top dropdown, select “Make Sequential” to batch renames files.
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• You will be shown totally different options to choose from. From this options choose “Add Numbers to” “new name” and leave the rest default.
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• Click on the “Options” at the bottom of this flow and tick “Show this action when the workflow runs”
• 

Now, save this workflow somewhere on your Hard drive with your desirable name. Once you saved your Workflow, Save As again as an Application. Simply Files > Save as… and select Application in the Save dialog.

If you want, you can make a shortcut for this Application on your Dock. This way, you can simply drag and Drop the Files into your Dock Icon Directly. Or you can always drop the files on Application (Wherever it is).

When you drop Files, Workflow will begin and filter out all files and select images to rename. Once it’s finished filtering, it will show you the Rename option to enter new name and make other changes before rename.

Hope this helps you with what you’ve looking for! There are lot of things you could do with Workflow, do explore and play-around and see what can you do?