How to change the title color of EKEventViewController in iOS 13?

Question

It is private class called EKCustomTitleView. And you cannot imagine the "Event Details" is UIImageView instead of UILabel.

appearance.titleTextAttributes = [.foregroundColor: myAppLabelColor]
appearance.largeTitleTextAttributes = [.foregroundColor: myAppLabelColor]

I try to add this, but it cannot work.