Well if a Wii U version won't sell, I guess a Wii version will!
FIFA 15 is making its way to the Wii and 3DS, though no version for the Wii U.
While FIFA 15 for "next-gen" systems has multiple new features to set itself apart from previous entries, the Wii and 3DS versions most likely only have an updated roster as their selling point. The press release states "Not all game features are available on all gaming platforms." This is not new territory for Electronic Arts, last year's FIFA 14 on Wii and 3DS, was subtitled "Legacy Edition" and had no updates to gameplay or game modes.
FIFA 15 is coming to almost every platform, except for Wii U, releasing this fall.