`JsonKey.fromJson` seems to be ignored

My code:
```dart
@JsonSerializable()
class Person {
@JsonKey(
fromJson: unixTimeToDateTime,
toJson: dateTimeToUnixTime,
includeFromJson: true,
includeToJson: true,
)
DateTime dateOfBirth;

Person({required this.dateOfBirth});
}

DateTime unixTimeToDateTime(int secondsSinceEpoch) =>
DateTime.fromMillisecondsSinceEpoch(
secondsSinceEpoch * 1000,
isUtc: true,
);

int dateTimeToUnixTime(DateTime dateTime) =>
dateTime.millisecondsSinceEpoch ~/ 1000;

```

Generated:
```dart
Person _$PersonFromJson(Map json) => Person(
dateOfBirth: DateTime.parse(json['dateOfBirth'] as String),
);
```

Any solution?

UPDATE:
`JsonConverter` is not a solution because in many cases I need to specify the `JsonKey.name` too.