AuthUser.php

<?php
// Application/Entity/AuthUser.php

namespace Application\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity
 */
class AuthUser { }

config.php

<?php

return [
    'doctrine' => [
        'connection' => [
            // First connection
            'orm_default' => [
                'driverClass' => \Doctrine\DBAL\Driver\PDOMySql\Driver::class,
                'params' => [
                    'host'     => 'localhost',
                    'port'     => '3306',
                    'user'     => 'username',
                    'password' => 'password',
                    'dbname'   => 'database',
                    'diverOptions' => [
                        PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8mb4'
                    ],
                ],
            ],
            // Second 
            'orm_regauth' => [
                'driverClass' => \Doctrine\DBAL\Driver\PDOMySql\Driver::class,
                'params' => [
                    'host'     => 'localhost',
                    'port'     => '3306',
                    'user'     => 'username',
                    'password' => 'password',
                    'dbname'   => 'database',
                    'diverOptions' => [
                        PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8mb4'
                    ],
                ],
            ],
        ],
    ],
];

module.config.php

<?php 

return [
  // ...
  
  'doctrine' => [
        'driver' => [
            'user_entities' => [
                'class' => 'Doctrine\ORM\Mapping\Driver\AnnotationDriver',
                'cache' => 'array',
                'paths' => [
                    __DIR__ . '/../src/Entity'
                ],
            ],
            'orm_regauth' => [
                'drivers' => [
                    'User\Entity' => 'user_entities',
                ],
            ],
        ],
    ],
  
];