It sounds like you should not expect too many classic Resident Evil characters to show up in the game.
Resident Evil 7 promises to be a return to the horror roots of the franchise, after a few installments had an increasingly misguided focus on action. However, just because it is returning to the franchise’s tonal roots does not mean that it will also necessarily return to the franchise’s classic mythos. In fact, in spite of Capcom hinting at classic character cameos for Resident Evil 7, they are now looking increasingly unlikely.
Matt Mercer, the voice actor who plays Leon S. Kennedy in the Resident Evil franchise, recently spoke about a potential appearance in Resident Evil 7 to GameSpot, noting that Capcom seem to be cutting back on classic character cameos in the game.
“As far as 7 goes, I think they’re scaling back a little bit on throwing in all the classic cameos, I can say that I don’t have any involvement in 7 directly,” he said. :But I think it’s also good of them, especially coming off of [Resident Evil 6] and its lukewarm reception, to go ahead and reestablish their roots and maybe start an original story, and if they decide that that does well, maybe they can then marry it in with the previous stories.”
While this is definitely a bit of a bummer, I can also agree with Mercer’s take on the situation. Given how poorly received some recent installments in the series have been, and also given how much of a dramatic break the new game seems to be, it makes sense that Capcom would want this game to strike out on its own for now- so that if it fails, the rest of the franchise remains insulated from it, and if it succeeds, they can then integrate it with the rest of the franchise later.