Hello,
Thank you for getting in touch with us.
Rank Math helps you add the proper Schema to tell Google about your logo as well as the featured image you are using for a particular post.
You can verify the same here:
https://search.google.com/test/rich-results
However, there is much to show the images in SERPs than having the correct Schema. Google picks that automatically for the keyword where it makes sense. They are also very picky about which websites get to show the thumbnails in the SERPs.
The option in the other SEO plugin you are talking about is most likely just the preview that shows up just for the author of the post in the WP backend. Do let us know if you mean something else.
