Anyone opting to pick up the disc version of The Legend of Zelda: Breath of the Wild on Wii U will be faced with a mandatory installation, though it won't require quite as much space as the digital version.
Breath Of The Wild Wii U Download
According to the Nintendo of Japan page for the game (via Nintendo Everything), a select amount of data needs to be installed to the system or an external storage device. Specifically, you'll need to install 3 GB's worth of data to play the game. It's unclear what exactly this is for or if, like with Xenoblade Chronicles X, there will be additional, optional files you can install to expedite load times.
By contrast, the digital version of Breath of the Wild on Wii U takes up 13 GB. The digital Switch version requires 13.4 GB, which is a fairly substantial portion of the system's internal storage. Its capacity can be expanded with microSDXC cards, while the Wii U allows you to use an external USB hard drive.
Purchase the Expansion Pass for The Legend of Zelda™: Breath of the Wild. These are the ONLY ways to purchase the Expansion Pass for Wii U. For the Nintendo Switch version, 2.4 GB of storage is required to download and play both.
Zelda Breath Of The Wild Wii U Free Download
Breath of the Wild was recently confirmed as a Switch launch game, debuting for both that platform and the Wii U on March 3. You can read more about the various special editions here.