model in controller with required fields

[iBelow]

hi, i have a model like a:

class HubStats {
  HubStats({
    required this.timestamp,
    required this.news,
  });

  final DateTime timestamp;
  final List<News> news;

  factory HubStats.fromJson(Map<String, dynamic> json) => HubStats(
        timestamp: DateTime.parse(json["timestamp"]),
        news: List<News>.from(json["news"].map((x) => News.fromJson(x))),
      );
}

then i trying create a controller

class HubController extends GetxController {
  var isLoading = true.obs;
  var retiviedInfo = <HubStats>[].obs;  //fix

  //add init

  //add fetch

  void fetchData() async {
    try {
      isLoading(true);
      //TODO: change PC to dynamic (enum) platforms
      var stats = await fecthHubStats(platform: 'pc');
      retiviedInfo.assign(stats);
    } finally {
      isLoading(false);
    }
  }
}

but how i can declare a empty instance of HubStats with obs,

declare:
var value = HubStats(required field1, required field2 .......required field999999).obs;
.......

fetchdata method:
value  = info_from_api_requires

what if there are 100 required fields? not to prescribe them manually empty values? Or do I need to make optional fields?