Excludes Post IDs from Jetpack news sitemap

functions.php

/**
 * Excludes Post ID from Jetpack's news sitemap.
 * 
 * @param bool $skip
 * @param  WP_Post $post
 *
 * @return bool
 */
function jpc_exclude_post_from_news_sitemap( $skip, $post ) {
	if ( ! $post instanceof WP_Post ) {
		return $skip;
	}

	// Make sure you've PHP 5.4
	$excluded_post_ids = [9999, 9998];

	if ( in_array( $post->ID, $excluded_post_ids, true ) ) {
		$skip = false;
	}

	return $skip;
}

add_filter( 'jetpack_sitemap_news_skip_post', 'jpc_exclude_post_from_news_sitemap', 10, 2 );