Hi Martin,
To display the date field in another language, please enable the setting timestamp, change the site language in Settings > General.
Then use the WordPress function date_i18n() to display the date in localized format.
$value = rwmb_meta( $field_id );
echo date_i18n( 'F j, Y', $value );
Refer to this topic https://support.metabox.io/topic/problem-displaying-images-videos-and-date-format-in-french/
In case of using Oxygen builder, you need to contact Oxygen support to ask to implement the code.
.
