没有内置的方法，但是我能够通过一个指令实现预期的结果

import { Overlay, OverlayRef } from '@angular/cdk/overlay';
import { ComponentPortal } from '@angular/cdk/portal';
import {
  ChangeDetectionStrategy,
  Component,
  Directive,
  Input,
  OnInit,
  TemplateRef,
  inject,
  DestroyRef
} from '@angular/core';
import { takeUntilDestroyed } from '@angular/core/rxjs-interop';
import { IonModal } from '@ionic/angular';
import { CommonModule } from '@angular/common';

@Directive({
  selector: 'ion-modal[appIonModalOverlay]',
  standalone: true,
})
export class CosIonModalOverlayDirective implements OnInit {
  @Input({alias: 'cosIonModalOverlay', required: true}) overlayTemplate!: TemplateRef<unknown>;

  private overlayRef?: OverlayRef;

  private readonly _ionModal = inject(IonModal);
  private readonly _overlay = inject(Overlay);
  private readonly _destroyRef = inject(DestroyRef);

  ngOnInit() {
    this._ionModal.ionModalWillPresent
      .pipe(takeUntilDestroyed(this._destroyRef))
      .subscribe(() => {
        this.open();
      });
    this._ionModal.ionModalWillDismiss
      .pipe(takeUntilDestroyed(this._destroyRef))
      .subscribe(() => {
        this.overlayRef?.dispose();
        this.overlayRef = undefined;
      });
  }

  private open() {
    if (this.overlayRef) {
        if (ngDevMode) {
            throw new Error('OverlayRef already exists');
        }
        return;
    }
    this.overlayRef = this._overlay.create({
      positionStrategy: this._overlay
        .position()
        .global()
        .centerHorizontally()
        .bottom('0'),
    });

    const componentPortal = new ComponentPortal(ModalControlsContainerComponent);

    const ref = this.overlayRef.attach(componentPortal);
    ref.instance.template = this.overlayTemplate;
  }
}

@Component({
  selector: 'app-ion-modal-controls-container',
  changeDetection: ChangeDetectionStrategy.OnPush,
  template: `<ng-container *ngTemplateOutlet="template"/>`,
  imports: [CommonModule],
  standalone: true
})
export class ModalControlsContainerComponent {
   @Input() template!: TemplateRef<unknown>;
}

用法非常直接

<ng-template #modalFooterControls>
  This will be rendered as a footer of the modal. Styles from the host component will also be applied
</ng-template>

<ion-modal [appIonModalOverlay]="modalFooterControls"...>
  ... 
</ion-modal>