How to custom Switch to bind value as string "Y" and "N" instead of bool ture/false?

Better approach will be to exerted your data model with additional boolean property that will get/set the original string property. Check this article for more info:

Thanks for extending model with additional property advice.

What if to custom radio button list?
Since we have common baseline to use components to complete mentioned project. They want to have Switch for their Y/N data, just like phone app settings, even browsers settings everywhere nowadays.

My first proposal was traditional Y/N dropdown list, but they want to have a clear visual effect.

Not sure I understand the problem. If your data are strings you can use additional properties to wrap them in boolean or whatever type - for example integer foe radio button list values

I prefer to have a component like Switch can bind value with "Y" and "N" directly.
For some other cases, some component like Switch can bind value with 1 and 0 directly is desirable.

I’m afraid that we don’t have such component.

Noted, thanks for understanding!