[Solved]-error NG6001: Cannot declare 'Highchar tsChartComponent' in an NgModule as it's not a part of the current compilation-Highcharts

The problem could be with Ivy compiler, in Angular AOT compilation Ivy is used by default. Try to disable Ivy in tsconfig.json:

{
  "angularCompilerOptions": {
    "enableIvy": false
  }
}

In my case, the issue was that I try to declare component in different place then I created it, in the different module different folder. So you need to add module near your component, add this component into created module, then in the module where you tried to declare your component just import created module which contains required component.

Answer found here: https://github.com/angular/angular/issues/37047#issuecomment-634226777

You should only import the module in imports, not declare any specific component in declarations:

@NgModule({
  declarations: [
    AppComponent,
  ],
  imports: [
    BrowserModule,
    HighchartsChartModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }