actuel-inactuel/site/config/routes/virtual-category.php

<?php

use Kirby\Uuid\Uuid;

return [
  'pattern' => 'categories/(:any)',
  'action'  => function ($category) {
      return Page::factory([
          'slug'     => Str::slug($category) . '-' . Uuid::generate(),
          'template' => 'category',
          'model'    => 'category',
          'content'  => [
              'title' => $category,
              'uuid'  => Uuid::generate(),
          ],
      ]);
  }
];