It's easy to disable disable WooCommerce products from being shown as Fomo notifications.
Navigate to your WordPress > Admin > Products section.
Click to Edit the product you want to exclude.
In the Product Data section, click on Attributes, then Custom Product Attribute > Add.
Input "fomo-ignore" as the attribute name, with a Value of 1.
You're done! New sales of this product will no longer become Fomo notifications.