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You would have to contact those providers. Roku does not create the channels that are available (other than The Roku Channel and Roku Media Player). It is up to a provider to decide they want to offer a Roku channel, and they are also the only one that can decide which Roku devices they will support and what geographical locations their channel will work.
Dan Roku Stick (3600), Ultra (4640), Ultra (4670), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.