Meta_Query with Custom Tables and Orderby

Hi,

No, it is not supported to use custom table meta with WP Query. You can query posts by getting the post IDs in the custom table.

global $wpdb;
$ids = $wpdb->get_col( "SELECT ID FROM your_table WHERE field1 = 'value1' OR field2 = 'value2'" );

if ( empty( $ids ) ) {
    echo 'There is no posts';
} else {
    $query = new WP_Query( [
        'post_type' => 'post',
        'post__in'  => $ids,
    ] );
    // Do something
}