Adding a Facebook video to your product gallery images is easy using the WooGallery plugin. Follow the steps below: 

1) From the Edit Product page scroll down to the Product Gallery area.

2) If you want to add the Facebook video to the Featured Image, click on the featured image. If you want to add the video to a gallery image, click on Add product gallery images. This will open the Media Library, where you can select the gallery image. 

3) Once you select an image, a popup (Attachment Details) will appear where you will see a box named Video Link at the bottom. 

4) Insert the Facebook video link there, and the video will be set with that image.

Note: The Facebook video URL should be copied from the Embed video.

1. Click on Embed from the three dots.

2. A popup will appear as Embed Video.

3. Click on Copy Code.

4. Then paste the code in the WooGallery Video Link field and keep only the link that is in the first inverted comma and remove all the other text. See the following screenshot:

Note: For your convenience, you can paste the embedded code into a text editor, keep only the URL, and remove the other text.