Sticky posts limit query and pagination for a custom post type

Question

I would like to display 9 posts per page. But, when I have a sticky post, I would like it to be integrated in the 9 posts in the query. And, then, for the second page, I continue to have the next 9 posts... So I did this:

$sticky_count = count(get_option( 'sticky_posts' ));
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$posts_per_page = 9;
if(!is_paged()):
   $posts_per_page = $posts_per_page - $sticky_count;
endif;
$params = ['post_type' => 'projects', 'order' => 'DESC', 'posts_per_page' => $posts_per_page, 'paged' => $paged];

$my_query = new WP_Query( $params );?>
<?php $c_array = $my_query->get_posts(); ?>
     <?php foreach ($c_array as $project) : ?>
           <div class="cell small-12 medium-6 large-4">
                <?php include locate_template('parts/one_project.php'); ?>
           </div>
    <?php endforeach; ?>

With this code, I have 9 posts on my first page, including the sticky post. I also have 9 posts on the other pages. However, one post is missing!

Let's say I put the 14 in sticky. So on my first page I have: 14, 1, 2, 3 ... 8. On the second page, it's the 10th post that appears. The ninth has disappeared... How to do ?

Thanks a lot for help

EDIT --- I tried to do that but I still have the problem since the request is re-executed on each page...

$sticky = count(get_option('sticky_posts'));
$posts_per_page = 9;
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$params = [
    'post_type' => 'projects',
    'order' => 'DESC',
    'posts_per_page' => $posts_per_page,
    'paged' => $paged,
    'offset' => 9 - $sticky
];
if (!is_paged()):
    $posts_per_page = 9 - $sticky;
    $params = [
        'post_type' => 'projects',
        'order' => 'DESC',
        'posts_per_page' => $posts_per_page,
        'paged' => $paged,
    ];
endif;