Para mockar a API utilizei o mockoon (https://mockoon.com/), basta importar o arquivo mockoon.json dentro do mockoon Rodar flutter pub get
Trocar baseUrl no app_module.dart apontando para o endereço da sua API
@override
List<Bind> get binds => [
$UserStore,
$UserService,
$UserRepository,
$AppController,
$CustomDio,
$LoadingDialog,
Bind(
(i) => BaseOptions(
baseUrl: 'http://192.168.15.12:3001/',
connectTimeout: 5000,
),
),
];
@override
List<Router> get routers => [
Router(Modular.initialRoute, module: LoginModule()),
Router('/home', module: HomeModule()),
];
@override
Widget get bootstrap => AppWidget();
static Inject get to => Inject<AppModule>.of();
}