以下、今回の構成。
ContainerViewController に UIScrollView がある
└ NavigationViewController(ScrollViewの中にあるContainerView内に設定)
└ ParentViewController
└ ChildViewController ─ swipeRecognizerToLeft(左スワイプのジェスチャー)
└ swipeRecognizerToRight(右スワイプのジェスチャー)
let parentVc = self.navigationController?.viewControllers[0]
let NavigationVc = parentVc?.parent
let containerVc = NavigationVc?.parent as? ContainerViewController
containerVc?.scrollView.gestureRecognizers?.forEach({ gesture in
gesture.require(toFail: swipeRecognizerToLeft)
gesture.require(toFail: swipeRecognizerToRight)
})