angular component refactoring from many input properties to a single input config object

One option would be putting the state into a Service and using it to update the component. Services are a great way to extract logic from other parts of the app and have it in central locations. So instead of using inputs, you just declare the variables in your component, then whenever you need to pass the data to the component you just call a method in the service that emits the inputs, (whose state is taken care of in the service) you need. In the component's constructor you pass it in as a private parameter (the private part is very important). Implement OnInit from angular/core and subscribe to the method, and in the subscription you use a function to update the variables. If you see yourself using the inputs elsewhere you might want to create a data object as well as passing one object is much easier than passing in multiple variables.

Component Pseudocode:

@Component(... some stuff here ...)
export class YourComponent implements OnInit{ //don't forget to import OnInit
vars: varTypes;

constructor(private yourComponentService YourComponentService) {}
ngOnInit(){
    this.yourComponentService.getVars.subscribe((vars)=>this.vars = vars);
}

Service Pseudocode:

@Injectable({ 
    providedIn: 'root'
})
export class YourComponentService {
  gettingVars = new EventEmitter<varTypes>();
  private vars: varTypes = x;

  public getVars() {
    this.gettingVars.emit(vars);
  }

  public setVars(vars: varTypes) {
     this.vars = vars;
     getVars();
  }
}

It depends on what your data is and how is it related. Its pretty much not an angular question but about data modeling.

In general, group together data that makes sense together.

For example, if you have child that needs firstName, lastName, address, age for some person, it wouldn't make sense to send 4 @Inputs. You would rather create new type Person with those 4 properties and send whole Person as a single @Input.

Now, if same component needs totalNumberOfPersons, it wouldn't make too much sense to pack that int into Person type but you would be sending that one as a separate @Input; so you would end up with 2 @Inputs:

@Input()
person: Person

@Input()
totalNumberOfPersons: int

just add it and be done with it. 5 input properties is not a lot.