Hi,

Please install the Code Snippet plugin, then create a new snippet with the following content:

function pcremove_custom_fields_filter( $meta_excludelist ) {
    // Merges the defaults array with our own array of custom fields.
    return array_merge( $meta_excludelist, [ '_post_like_count' ] );
}
add_filter( 'duplicate_post_excludelist_filter', 'pcremove_custom_fields_filter' );

Regards,
PenciDesign.