tramacriacoes

My solution:

add_shortcode('recent_posts_week', 'shortcode_recent_posts_week');
function shortcode_recent_posts_week() {

$the_query = new WP_Query( 'cat=noticias-semana' ); 

	if ( $the_query->have_posts() ) : 

		$html = '<div class="container">';

		while ( $the_query->have_posts() ) : $the_query->the_post(); 

			if($sinaval_post_year != get_the_date( 'Y' )) {
				$html .= '<h2><a href="'.site_url().'/'.get_the_date( 'Y' ).'">'.get_the_date( 'Y' ).'</a></h2>';
			};
			if($sinaval_post_week != get_the_date( 'W' )) {
				$html .= '<h3>From '.date('j/M/Y',strtotime(get_the_date( 'Y' ).'W'.get_the_date( 'W' )));
				$html .= ' til '.date('j/M/Y',strtotime('this friday '.get_the_date( 'Y-n-j' ))).'</h3>';
			};
			$sinaval_post_year = get_the_date( 'Y' );
			$sinaval_post_week = get_the_date( 'W' );

			$sinaval_post_format = get_post_format(get_the_ID());
			if($sinaval_post_format == "link") {
				$html .= '<h4><a href="'.get_the_content().'" target="_blank">'.get_the_title().'</a> </h4>';
			} else {
				$html .= '<h4><a href="'.get_permalink(get_the_ID()).'">'.get_the_title().'</a></h4>';
			};
			$html .= '<ul class="meta">';
			$html .= '<li><span class="date">'.get_the_time('j/n/Y').'</span></li>';
			$html .= '</ul>';

		endwhile;

	$html .= '</div>';

	wp_reset_postdata();

	return $html;

	endif;
}

Turns out I didn’t need the date_query at all, just some php’ strtotime and wordpress’ get_the_date.

Since Alex, said it was not easy, I think I’m missing something here, but the code is working well (still needs some testing).

But thanks for the quick response!