html content between posts on the blog page

I would like to place some html content between posts on the blog page. I tried to do so. Are there any other ideas? Or is it better to write code in content-blog.php?

// Add content to astra_entry_after()
add_action( 'astra_entry_after', 'add_content_entry_after' );
function add_content_entry_after() {
global $wp_query;
if($wp_query->query['pagename']=='blog'){
?>
      <!-- Your HTML goes here -->
<?php}  
}