PS4
The Order: 1886
Bloodborne
Fat Princess Adventures
Everybody's gone to the Rapture
Drawn to Death
Alienation
Until Dawn
The Tomorrow Children
Onechanbara Z2 Chaos
N++
Disgaea 5
Hotshots Golf
Let it Die
Guns Up!
Killstrain
Omega Quintet
Brawl
=
17 in total.
Wii U
Captain Toad: Treasure Tracker
Fatal Frame V
Kirby and the Rainbow Curse
Super Mario Maker
Mario Party 10
Splatoon
Star Fox Zero
Mario Tennis: Ultra Smash
Xenoblade Chronicles X
Yoshi's Woolly World
Dvils Third (despite the bastard PC version)
Fast Racing Neo
=
12
Xbox One
#IDARB
Forza 6
Halo 5
(that didn't take long ^^)
=
3
That makes 17 PS4 exclusives 2015.
And 12+3 = 15 exclusive games on Wii U and Xbox One.
The Wii U version of Rodea The Sky Soldier is not as different to the 3DS version as you have implied. Otherwise Tearaway Unfolded is to be included too.
As for Q4 2015. It's actually not as easy to determine, since there are no specific release date for some games. However, "for the rest of the year"? If you say so...
PS4
Disgaea 5
Alienation
Let it Die
Guns up!
Kill Strain
Tomorrow Children
Fat Princess Adventures
Drawn to Death
Hot Shots Golf
=
9
Wii U
Star Fox Zero
Mario Tennis: Ultra Smash
Xenoblade Chronicles X
Fast Racing Neo
=
4
Xbox One
Forza 6
Halo 5
=
2
9:6 so far (9:7 incl. Yoshi's Woolly World, since a backwater country called US of A hasn't got a release yet ;D ).
Phew, lucky PS4. Got pretty close their in this 2 vs. 1 contest.