Flutter: Get currently active TextEditingController without explicitly creating Controllers or Nodes

Question

ATTENTION: Windows-Development here.

I want to use a virtual keyboard (on screen). I can not rely on a hardware-keyboard.

My goal is to securely get any TextEditingController if I e.g. tap on a TextFormField so I can use it in my virtual keyboard (I use this plugin).

Currently my VirtualKeyboard is wrapped in a Stack as a Positioned and only shown if a Focus-change has been detected. This already works:

Focus(
    onFocusChange: ((value) {
      BlocProvider.of<KeyboardCubit>(context).setShow(value);
    }),
    child: Stack(...),
)

But I'm stuck on the part to get the TextEditingController. I do not want to add custom code for every TextFormField. Flutter achieves it somehow when pressing on something that may be focusable, so why can't I?

Maybe I am missing something. I am glad to hear your opinions.

Best regards.

Alternative Question: Is there any good Virtual Keyboard plugin that handles this use case safely?