What are region settings and why do they matter?
Each Plex Media Server attempts to identify in which country or world region it is located. Sometimes the automated region identification fails and users need to manually set the region to ensure the best user experience.
Due to restrictions from content providers, some Plex channels will not work outside of specific regions. As such, those channels are hidden from view in the Channel Directory unless the region setting identifies the user as being located within the allowed region.
How do I set the region on Plex?
You can always access region settings for your Plex Media Server through the Plex Web App. It is the Region preference under Settings > Server > Channels.
Alternatively, using Plex Web App, you can open Channels, then use the Install Channels button to open the Channels admin interface. Here, you can go to More... > Preferences... to access the Region setting.
Understand that the region setting does not act like a proxy or VPN. That is, while setting it to a region other than your own will allow you to install channels restricted to that region, it will not make the channel work or play videos that are region-restricted. The region setting in Plex Media Server simply makes sure that the channels shown in the Channel Directory are the ones appropriate for that region.
Note: Very rarely, updates to Plex Media Server can reset the selected region to "Automatic", which may necessitate you selecting your appropriate region again.
Related Page: Server Settings > Channels