KOS-MOS has potentially been found on the banner leak! Don't know why it took so long but it did, she's right above Ken, Diddy Kong and Pit have been moved diagonally left behind Ken and Shiek has been moved diagonally down left to Yoshi, so she's right next to Yoshi who was moved in front of Ken and under KOS-MOS, and KOS-MOS is above Yoshi and Ken. Of course though there is a possibility our eyes are being tricked and it's just the cloud formation, but there's a higher chance its KOS-MOS since why would those characters need to be moved from their top positions?
Further more this lines up with the OG corocoro leak of 108 stages in total.
As we have seen with Simon and Richter echos and original fighters can share home stages, so no new Street Fighter stage.
Shadow will get Windy Hill Zone, so no new Sonic stage.
So far with the echo fighters we have 103 stages still.
Now with the original fighters...
Seeming as there are plenty of Mario stages without characters tied with them yet and this one stage is tied heavily with the RPG spin-offs of Mario, Geno will probably get the Paper Mario stage, so no Super Mario RPG inspired stage so we're still at 103.
Thus we're left with the unrepresented series: Banjo and Kazooie = 1 new stage, Mach Rider = 1 new stage, Rythm Heaven (Chorus Kids) = 1 new Stage, Golden Sun (Issac) = 1 new stage, and Xenosaga (KOS-MOS) = 1 new stage. Even then if KOS-MOS was counted as Xenoblade rep she'd get a new stage regardless as we haven't seen same unique fighters sharing the same stage.
With all this information... we have the five characters needed to bump that 103 stage count to the 108 corocoro leaked to us, it makes sense as well as of course, unrepresented series require brand new stages than existing ones that don't tie to their series.
This is the end of these spoilers, feel free to spread and share it around if you want just don't go too crazy and ruin the direct tomorrow for people.