Display last posts with wp_query using meta value & groupby

Hello,

I’m trying to regroup posts containing different meta values & to display only last posts written for each meta value.

So I wrote this piece of code :

add_filter('posts_groupby', 'query_group_by_filter');
 	function  query_group_by_filter($groupby){
       global $wpdb;
       return $wpdb->postmeta . '.meta_value';
    }

	// WP_Query arguments
	$args = array (
		'post_type' => 'post',
		'post_status' => 'publish',
		'order' => 'DESC',
		'orderby' => 'date',
		'meta_query' => array(
		      array(
		      'key' => 'article_information_artiste',
	       	),
	    ),
	);

	// The Query
	$query = new WP_Query( $args );
	// The Loop
	if ( $query->have_posts() ) {
		while ( $query->have_posts() ) {
			$query->the_post(); ?>
			// Do something
		<?php }
	} else {
		echo "No content!";
	}

	remove_filter('posts_groupby', 'query_group_by_filter');
	// Restore original Post Data
	wp_reset_postdata();

It regroups posts with specific meta values but it displays only the first post, not the last one.

I try to add to the wp_query order & orderby argument but nothing happens.

Do you know how to display only last post written for each meta value ?
Here a preview

Thanks for your help.