I bet the Wii U wont even be mentioned at E3.

[maxleresistant]

The main thing is that there won't be enough WiiU titles to have a focus on it. The 2015 E3 was already a sad show.
So they will just show what there is left, all mixed with the 3DS and NX titles, but I bet the Zelda presentation will focus on the NX version.