In case anyone is interested doing this on PS8.1, you just have to edit "/classes/Address.php" file.
Here you can change the "size" value:
// when you override this class, do not create a field with allow_null=>true
// because it will give you exception on checkout address step
public static $definition = [
'table' => 'address',
'primary' => 'id_address',
'fields' => [
'id_customer' => ['type' => self::TYPE_INT, 'validate' => 'isNullOrUnsignedId', 'copy_post' => false],
'id_manufacturer' => ['type' => self::TYPE_INT, 'validate' => 'isNullOrUnsignedId', 'copy_post' => false],
'id_supplier' => ['type' => self::TYPE_INT, 'validate' => 'isNullOrUnsignedId', 'copy_post' => false],
'id_warehouse' => ['type' => self::TYPE_INT, 'validate' => 'isNullOrUnsignedId', 'copy_post' => false],
'id_country' => ['type' => self::TYPE_INT, 'validate' => 'isUnsignedId', 'required' => true],
'id_state' => ['type' => self::TYPE_INT, 'validate' => 'isNullOrUnsignedId'],
'alias' => ['type' => self::TYPE_STRING, 'validate' => 'isGenericName', 'required' => true, 'size' => 32],
'company' => ['type' => self::TYPE_STRING, 'validate' => 'isGenericName', 'size' => 255],
'lastname' => ['type' => self::TYPE_STRING, 'validate' => 'isName', 'required' => true, 'size' => 255],
'firstname' => ['type' => self::TYPE_STRING, 'validate' => 'isName', 'required' => true, 'size' => 255],
'vat_number' => ['type' => self::TYPE_STRING, 'validate' => 'isGenericName'],
'address1' => ['type' => self::TYPE_STRING, 'validate' => 'isAddress', 'required' => true, 'size' => 128],
'address2' => ['type' => self::TYPE_STRING, 'validate' => 'isAddress', 'size' => 128],
'postcode' => ['type' => self::TYPE_STRING, 'validate' => 'isPostCode', 'size' => 12],
'city' => ['type' => self::TYPE_STRING, 'validate' => 'isCityName', 'required' => true, 'size' => 64],
'other' => ['type' => self::TYPE_STRING, 'validate' => 'isMessage', 'size' => 300],
'phone' => ['type' => self::TYPE_STRING, 'validate' => 'isPhoneNumber', 'size' => 32],
'phone_mobile' => ['type' => self::TYPE_STRING, 'validate' => 'isPhoneNumber', 'size' => 32],
'dni' => ['type' => self::TYPE_STRING, 'validate' => 'isDniLite', 'size' => 16],
'deleted' => ['type' => self::TYPE_BOOL, 'validate' => 'isBool', 'copy_post' => false],
'date_add' => ['type' => self::TYPE_DATE, 'validate' => 'isDate', 'copy_post' => false],
'date_upd' => ['type' => self::TYPE_DATE, 'validate' => 'isDate', 'copy_post' => false],
],
];