Apple coded the ability to stream iTunes purchased TV/Movie content out of iOS sometime at some version of iOS 8.
I discovered this feature omission in iOS 9 when I started inquiring about this.
This was an undocumented and workaround feature, from iOS 5 to the last iOS 7 update, to be able to stream iTunes purchased movie/TV content remotely from an external storage device, but Apple closed down, coded out this ability/workaround since, and it seems that Apple is not going to restore this ability anytime soon!
There is no way to do this any longer!
There is NOTHING you can do to get this to work!
This ability is gone!
Plus, with mobile, portable, WiFi hard drives and mobile flash drives, you are forced to use a drive maker's app to access these drives and the drive app is not capable of wirelessly streaming purchased iTunes TV/ Movie content as Apple's own DRMs have been preventing this, too!
The remote streaming ability was accessed through a workaround that allowed streaming of purchased iTunes movie/TV content though the iOS Safari web browser.
Apple closed up, coded out this workaround out of Safari during an early iOS 8 update, forever preventing protected, BUT PURCHASED, iTunes movie/TV from ever being streamed from a remote storage device.
Android devices do not have this limitation to be able to stream the same iTunes purchased content to their devices from a wireless WiFi remote storage device.
The only thing you can do is transfer movies from the drive to your iPad to watch the movies off of your iPad, now!
The wireless drive is just a storage vessel, now and not an external streaming device.
Yes,
You can stream your own ripped movies from these wireless drives using the wireless drive maker's own app found in the iOS App Store.
I have resorted to stop purchasing any more iTunes movie/TV content and going back to purchasing physical muliti format discs of movies/tv show and creating my own digital copies of DVDs that I can use with both my Seagate Wireless portable drives and wireless and lightning connected mobile, portable USB flash memory drives.
I can now directly stream all of my movie/TV content, once again, from external storage devices.
You CAN stream downloaded YouTube content from remote wireless drives to your iPad, also.
I still own the first generation iPad that still has iOS 5.1.1 that still has this capability. So, I can still stream movies from my Seagate Wireless hard drive to my 2010 iPad 1, but this is my only iPad that still can do this.
If you want Apple to restore this external streaming workaround feature/ability, send feedback here.
iPad Feedback
http://www.apple.com/feedback/ipad.html
Good Luck!