Exactly as the title says, let's all share our top five favorite exclusives in 8 Gen Consoles. A few ground rules, though, since everyone has a different idea of what "exclusive" is now.

1. The title must be available on a single platform.

2. We'll be observing titles from Wii U, Switch, 3DS/2DS, PS4, Vita, XB1, and PC/Mac.

3. PC/Mac titles must have released after the launch of the 3DS to qualify.

Titles that have been suggested but don't qualify:

Mario Kart 8

Available on both Wii U and Switch.

Crash Bandicoot: N.Sane Trilogy

Available on PS1 separately.

Breath of the Wild

Available on both Wii U and Switch

Smash 4

Available on both 3DS and Wii U

Without PC or multiple console releases (Wii U and Switch) that leaves only a few Switch games and mostly non-Japanese PS4 games to choose from, so...

1. Bloodborne

2. Horizon Zero Dawn

3. Uncharted Lost Legacy - Uncharted 4

4. Until Dawn

5. Infamous First Light

Mario Kart 8 would be up there for me, but the only Switch exclusive I own that's not available on Wii U is Splatoon 2, and while that game is lots of fun, I wouldn't put it among my favorites. Super Mario Odyssey will likely be one of my favorites this gen, however (and hopefully Metroid Prime 4). 

That's a PS3/PS4 release.

1. Splatoon 2
2. TMS#FE
3. Splatoon
4. 3D World
5. MK8

Edit: #5 - Nintendoland 

Bloodborne
Pokemon X
inFAMOUS Second Son
Horizon Zero Dawn
inFAMOUS First Light

If it's available elsewhere is the same style, no dice. But if gameplay has been radically altered to work with, say, touch controls then you're good to go.

MK8 was ported to Switch.

Wii U comepted with PS4 and XB1. 

Then I guess 

#5 Nintendoland 

You're right, forgot about that. 

All right, I guess I'll throw in Infamous First Light at 5 and bump up the others in Persona's place. 

Pokemon Sun
Splatoon 2
Fire Emblem Awakening
Captain Toad
Mario 3D world