Field::copy

public function copy($iblockId, $copiedIblockId): Result
{
	$fields = $this->getFieldsToCopy($iblockId);
	$this->addFields($copiedIblockId, $fields);

	$properties = $this->getProperty($iblockId);
	$this->addProperties($copiedIblockId, $properties);

	return $this->result;
}