Nordic One IPTV on Apple TV
Short version: it is not available, and no workaround changes that. Here is why, and what people do instead.
Short answer
There is no tvOS version of Nordic One IPTV and it is not on the Apple TV App Store. To use it on the same television, connect an Android TV device or a Fire TV device to a spare HDMI port.
Why it is not available
tvOS only allows applications distributed through the App Store, and there is no sideloading route for ordinary users. The developer has not published a tvOS version, so there is nothing to install.
What to do instead
- Add a Firestick, Fire TV or Android TV box on another HDMI input and switch between them.
- Use a different IPTV player that does have an Apple TV release, with the same playlist.
Your plan still applies
Streaming access is not tied to a particular application, so switching player does not affect your plan. Only the number of devices matters.