columnsOverrides not possible for type group
It's not possible to overwrite configuration of columns of type group via columnsOverrides.
It partially works, but not for the data source.
Due to configuration in formEngine.formDataGroup.tcaDatabaseRecord the order is wrong.
\TYPO3\CMS\Backend\Form\FormDataProvider\TcaColumnsOverrides::class is called after \TYPO3\CMS\Backend\Form\FormDataProvider\TcaGroup::class.
While it would be easy to adjust order, it's in fact not. TcaColumnsOverrides does need \TYPO3\CMS\Backend\Form\FormDataProvider\DatabaseRecordTypeValue which in turn needs \TYPO3\CMS\Backend\Form\FormDataProvider\TcaGroup::class again.
This way one can not re-use the records column of tt_content for any other record. While it works while selecting entries, it does not work either for suggest nor for re-display in backend. As always the original tt_content records are fetched for persisted IDs.