
Firstly, we would like to thank to Martin Stehle, who has developed this very awesome plugin, Quick Featured Images. It is been a really helpful to us as we only spent less than 5 minute to perform this whole activity. I remember spending nearly 3 days of manually changing the featured images, 5 years ago!
So, in this article example, we want to perform mass add to the featured image for the SAP SOLMAN category. No featured image visible for SAP SOLMAN category as per below screenshot. Also, we have multiple featured images for SAP SOLMAN.

Note: No undo function. Please do a backup of the WordPress database before you perform below activity.
Step 1: Add Quick Featured Images plugin, install and activate in your WordPress website. Go to Bulk Edit and you will notice there’s a Progress bar on the right panel. Each bar will provide you, the list of selections and actions that shall be taken before you can proceed to the next one.

Step 2: Select Set multiple images randomly as featured images, under Actions with multiple images. Click Next.

Step 3: Under Add Filter bar, select these options.
Optional: Select options
- Consider only posts without any featured image: Posts with featured images will be ignored, even if the Overwrite option is checked
Optional: Add a filter
- Category Filter: Search posts by category
Step 4: Select the category, under the Refine bar. Click on Preview filtering.

Step 5: You will see the list of post matches for the changes. You can edit a post in a new window by clicking on its link in the list.

Step 6: If confirmed, click on Apply. That’s it. Super cool, isn’t it?

The result,


