I’ve found that most plugins that optimize images duplicate images in new folders creating a superstructure that complicates the entire site. This plugin optimizes the images you have uploaded to your site and overwrites them. The thumbs are also regenerated. If the image is converted to webp or if the name of the image is changed, the system tries to correct the images already published in the articles and pages. However, it is possible to restore at any time. If you have space problems you can always delete the original image that is used for the restore

Yes, when you are in the setting activate “Resize when images are uploaded”

It supports jpg, webp and png formats in accordance with wordpress directives.

Yes, you can decide whether to compress high, medium or low quality images.

Yes if you haven’t removed the original image. Otherwise no.

Yes, you can select from the media library (list version) the images to be optimized, or use the hooks to extend the script.

You can customize which images to optimize and how, through ‘op_bir_resize_image_bulk’ filter.

Example

<?php 
/**
 * resize images uploaded
 * If it is a post it resizes to 800x800 pixels, if in the title there is no_compress it does not compress it.
 * @return  Boolean|Array [width:int,height:int]
 */
function fn_bir_resize_image ($filename, $attachment_id) {
    if (stripos($filename,"no_compress")) {
        return false;
    }
    $parent_id = wp_get_post_parent_id( $attachment_id);
    if ($parent_id > 0) {
        $post_type = get_post_type( $parent_id );
        if ($post_type == "post") {
            return ['with'=>800,'height'=>800, 'quality'=>80];
        }
    }
    return true;
}
// Called during bulk.
add_filter( 'op_bir_resize_image_bulk', 'fn_bir_resize_image', 10, 2);
?>

Hooks:
op_bir_resize_image_bulk_suffix returns the suffix to be added to the image
bulk-image-resizer-after-setup-form adds html to the end of the setting form

When you upload an image to wordpress, thumbs are created for the template, but the uploaded image is saved and sometimes used.
Bulk image resizer resizes uploaded images to optimize site speed and server space.

Be careful
If you remove the original images, The images are overwritten at the size you set, so it’s important to make a backup first.
They assume no responsibility for any malfunctions or loss of information resulting from the use of the plugin.