A closed network test for Tekken 8 was held in July, with an initial run that was exclusively available to Playstation 5 owners followed by a broader test that included players on Steam. Letting PC gamers near Tekken 8 meant that someone fired up Cheat Engine because of course they did, at which point they managed to find a partial roster in the game's files that includes six previously unannounced characters.
Those characters are Alisa, Raven, Shaheen, Steve, Yoshimitsu, and Zafina. By Raven they presumably mean the popular Blade-looking fighter added in Tekken 5, rather than Master Raven, his widely disliked replacement from Tekken 7.
As a former Yoshimitsu main I'm pleased to see his return, though not surprised. He's been in every mainline Tekken game since the original after all. Obviously this isn't a complete version of the roster as it excludes several other characters whose absence is unlikely, such as Kuma and Panda, as well as Robert "Bob" Richards, whose inclusion has been hinted at in the new Times Square stage.
Which means there's still a chance for Lucky Chloe to be part of the line-up, as well as whichever of your personal favorites hasn't been announced as being part of the Tekken 8 character list so far. They wouldn't include Nina Williams but leave out her sister Anna, would they?