I'm not sure about the question, but I think you could use DOM to get the element in component A at somewhere of component B's script. For example, inside component B's ngOnInit get some value from

document.getElementById("id in A html")

or

Use Service and power of Observable

@Injectable({
  providedIn: 'root'
})
export class TextService {

  textObserver: Observer<string>|undefined
  text: Observable<string> = new Observable()

  updateText(val: string) {
    
    if (!this.textObserver) {
      this.text = new Observable((observer: Observer<string>) => {
        this.textObserver = observer
        this.textObserver.next(val)
      })
      this.text.subscribe()
      return;
    }
    this.textObserver?.next(val)
  }

}

In somewhere of component A you can call updateText to set text and in component B you can do this.textService.text.subscribe(text => // your code) to get text and use in html view