Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
Installing a channel on any device on the same Roku account will install that same channel on all the devices. However, authenticating a subscription on one device does *NOT* carry over to other devices.
So, if you install FXNOW channel on the Roku Stick then it will also appear on the TV in the Living Room. This might give the impression other activity will also be copied between the device but that isn't true.
If you use your cable or satellite provider account to activate FXNOW to get full access to the channel on the Roku stick, then that activation is ONLY on the Roku Stick.
I am guessing the Living Room still has the channel in teaser/unsubscribed mode to let you see trailers for free but not be able to see full episodes. Check around the channel for a Sign In or Activate option. Once you have the Living Room TV also marked as being in a subscribed state, it should have access to all the same content.
It should also be noted that FX put in their user agreement that using multiple devices at the same time so if you accidently left something playing in one room and then played something from FX in the other room, maybe they enforce the user agreement by automatically de-authenticating one of the devices. But I am not completely sure how they enforce this rule (if at all).