These images appeared via 4chan last night, ostensibly from the instagram account of a worker from a French graphic printing company.
This would appear to be the completed "Everyone is Here" banner on a graphic to be used for shelving or a store display. It's in the usual potato quality as is customary for leaks, but outllined for clarity it looks like this:
Isaac, Geno, Mach Rider, Chorus Kids, and Banjo-Kazooie, with Ken and Shadow as Echo Fighters.
There are a couple of things grant some measure of legitimacy to this: First, the Instagram guy accidentally left his real name in the picture, which the anons tracked back to a linkedin profile for a French printing company that lists Namco-Bandai as a client. Since this surfaced, his linkedin has been deleted. Second, there has never been a clean image of the blank background for the banner released officially, plus all of the revealed characters have been cleanly rearranged to make room for the new ones.
Here's an image someone put together laying it all out, along with a few other pieces of information that would suddenly make sense if this was in fact the final rosters.
It's still possible this is an extremely elaborate fake, since anything is possible with the internet these days. But man, what a fucking pipe dream roster if this is true.