Developers can use the following filter:
/**
* Filters the post slug before it is generated to be unique.
*
* Returning a non-null value will short-circuit the
* unique slug generation, returning the passed value instead.
*
* @since 5.1.0
*
* @param string|null $override_slug Short-circuit return value.
* @param string $slug The desired slug (post_name).
* @param int $post_ID Post ID.
* @param string $post_status The post status.
* @param string $post_type Post type.
* @param int $post_parent Post parent ID.
*/
$override_slug = apply_filters( 'pre_wp_unique_post_slug', null, $slug, $post_ID, $post_status, $post_type, $post_parent );
It is then the programmer’s responsibility to ensure uniqueness of the slug.