Hugh Lashbrooke

Sick of adding a image to your post content then also setting it as the featured image in a separate action? Of course you are!
This plugin solves this problem by adding a new button alongside the “Insert into post” button in the media manager modal. When clicked, this button will insert your selected media and then, if you have selected an image, set that image as the post’s featured image.
It is possible to select multiple media items to insert, so this plugin will set the last image in the selected set as the featured image. The button will appear in the media manager modal for all post types.
This plugin works with WordPress 5.0+, but it will only work with Classic block or in the Classic Editor. It does not currently work with the Image block (or any other similar ones).
Want to contribute? <a href="https://github.com/hlashbrooke/Instant-Featured-Image" rel="nofollow ugc">Fork the GitHub repository</a>.
Got some great ideas? <a href="https://wordpress.org/support/plugin/instant-featured-image" rel="ugc">Post on the support forum</a>.

Instant Featured Image

Set an image as the featured image at the same time as you insert it into the post content.

Adam Ainsworth

Does exactly what it says on the tin, if you want your Featured Image to be inserted before the content in your pages or posts, and your theme doesn’t support this, then this is the plugin for you.
No styling is done by default, this will be added in a future version.

Thumbnail Before Content

This is a simple plugin that automatically inserts the post thumbnail (featured image) before the post content.

Instant Featured Image vs Thumbnail Before Content