A Brazilian hacking team recently released a method to run pirated Wii U games by utilising modified eShop tickets, apart from the piracy issue, you will also brick your console if you install the wrong region game, below is some important information:
*If you want to install on HDD, you need to format your HDD to WiiU format. Attention it will DELETE everything on that drive. DO NOT USE THE DRIVE YOU USE FOR vWII!
*In order to get your HDD to be recognized you may need to use a split USB cable
*The downloaded games need to be the region of your Wii U.
*The games will be playable online!
*You can install only ONE game at a time. You can of course have many installed games at the same time on your HDD or WiiU, but the installation process is done one by one!
*Purchased DLC and updates work fine
*You can transfer games installed to you Hard drive to your internal storage and it will run fine
*You can install games to internal storage without installing to USB
*If you have an existing savegame for your game on your internal storage, move it to you USB before installing the game to USB or you’ll lose it!
*To install your Loadiine save into the console, use Saviine homebrew. Guide available here