mrm_be/Configuration/TCA/Overrides/sys_file_metadata.php

<?php
$lll = 'LLL:EXT:mrm_be/Resources/Private/Language/locallang_ttc.xlf:sys_file_metadata';

$columns = [
    'copyright' => [
        'label' => $lll.".column.copyright",
        'config' => [
            'type' => 'input',
            'eval' => 'trim',
        ],
    ],
    'hasToBeSendToBA' => [
        'label' => $lll.".column.hasToBeSendToBA",
        'config' => [
            'type' => 'check',
            'renderType' => 'checkboxToggle',
            'items' => [
               [
                  0 => '',
                  1 => '',
               ]
            ],
        ],
    ],
];

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addTCAcolumns("sys_file_metadata", $columns);

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addFieldsToPalette(
    'sys_file_metadata',
    'mrm_be_imagemetadata_extension',
    'copyright'
);
\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addFieldsToPalette(
    'sys_file_metadata',
    'mrm_be_imagemetadata_extension',
    'hasToBeSendToBA'
);

\TYPO3\CMS\Core\Utility\ExtensionManagementUtility::addToAllTCAtypes(
 'sys_file_metadata',
 '--palette--;;mrm_be_imagemetadata_extension',
 '',
 'after:title'
);
/**/