ds-site/Configuration/TCA/Overrides/sys_category.php

<?php

declare(strict_types=1);

use TYPO3\CMS\Core\Utility\ArrayUtility;
use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;

(static function (string $tableName) {
    ArrayUtility::mergeRecursiveWithOverrule($GLOBALS['TCA'][$tableName], [
        'columns' => [
            'slug' => [
                'label' => '<path-to-locallang-file>.slug',
                'exclude' => 1,
                'config' => [
                    'type' => 'slug',
                    'generatorOptions' => [
                        'fields' => ['title'],
                        'prefixParentPageSlug' => true,
                        'replacements' => [
                            '/' => '',
                        ],
                    ],
                    'fallbackCharacter' => '-',
                    'eval' => 'uniqueInSite',
                    'default' => '',
                ],
            ],
        ],
    ]);

    ExtensionManagementUtility::addToAllTCAtypes(
        $tableName,
        'slug',
        '',
        'after:title'
    );
})('sys_category');