Hm, so it is one of the 8 big franchises after all. I just hope KI will get more love than just a highly modified Pit and some KI stages (that of which we only seen 1 of)... and a few items, hence the X-bomb. If they have shown Pit in that trailer with those Uprising weapons, I do expect KI to get a 2nd rep, aka, Palutena.
Theoretically speaking to say she was in, I don't think Palutena will be shown for a bit until character voices are done. iirc, each newcomer will get their own little entrance vid as you've seen WFT, Megaman, and Villager have. However, to make Palutena's vid tons effective, she, accompanied by Pit, need to bring some of that hilarious dialogue like they do in Uprising (and messing with Pit) to us. But it could happen December due to 12/19/86 being the KI anniversary, right? If I was to assume when this was to happen, I'd probably say during a December Nintendo Direct. Sure Sakurai could do it on 12/19 this year as it's a Thursday, but he does like to be unpredictable, so... Anytime this December is where I'm putting my hopes up. It'd be a great Holiday gift too if he did reveal the Goddess of Light during that time.