Nintendo Switch Controller delayed response on Android TV 9
Sadly this is an issue with Nintendo Switch Controllers
While Nintendo Switch Controllers use Bluetooth HID, they aren't completely conforming to the specification which means that you'll need a modified driver (and that is hard on Android).
Bluetooth HID (Human Interface Device) is the spec that allows for bluetooth keyboards, mice, and gamepads to communicate with supporting devices.
So I found this project trying to document the interface to the Nintendo Switch. As can be seen at the end of Issue #7 HID protocol for Bluetooth/USB there has been some success on Linux, but Issue #92 for Android has remained unanswered.
Changing the bluetooth driver is a Custom ROM level change. A compatible Android bluetooth driver would have to be made and support your bluetooth chipset and your platform hardware. As you are running TV hardware, I have doubts that any Custom ROMs exist, and then writing a driver supporting the Bluetooth chipset would be a further obstacle.
Based on:
Nintendo Switch Reverse Engineering HID Notes
Issue #7 - HID Protocol for Bluetooth / USB
Issue #92 - How to communicate with joycon in Android platform?