When you share an article on LinkedIn, the featured image does not appear, it shows the author image I set via gravatar instead. The og: image property has been set by the Yoast SEO plugin and it is working fine on Facebook. I need to have the featured image Open Graph appear on LinkedIn as well.
It seems to be related to the Yoast SEO plugin as we can see that the plugin is creating schema SEO information with yoast-schema-graph class and gravatar image link inside. Most likely Linkedin is reading it, so currently we can only recommend adjusting Yoast settings.