>>54308246>how do you find out who the new talents' past personas where before they even speak?>Are they doing something retarded like retweeting the hololive tweets with their old accounts?Yep, that's the way it usually goes. Happened this way with multiple talents in Holo, Niji and other corpos (basically anyone who's big enough to have enough eyes on them that people actually bother to properly scrutinize all this stuff).
Though it's less "talents blatantly following their new accounts with their old accounts", and more the "old acquaintances from the new talent's previous circle now following their new accounts" and similar third-party fuckups. These people usually don't mean any harm by it or actively WANT them to get doxxed, they probably even think they're doing a good thing by "showing support" or whatever. But it gives a breadcrumb trail that anyone remotely interested can easily follow to connect the dots back to their old friend group, see who recently graduated from there, and come to conclusions.
In some cases talents are especially retarded and even follow each other's private accounts mutually, so that when just one gets identified you have a chain reaction of the others being found as well because aww geez look at these 4 other random girls this account decided to follow during the pre-debut time that they never interacted with before, hmmm I wonder who they could be...
Other ways: especially for artists it often happens by comparing artstyles. You're a new pre-debut talent and you can only tweet, so you want to post some cute little chibi drawings or something. Well boom just five minutes later people have already found your old drawings and noticed the similarities, because no matter how small of an artist you were previously, if your art is on the internet, it takes just one out of the hundred thousand eyes you now have on you to go "hey, I remember that artstyle from somewhere..." and you're found. This is especially easy when you have distinct ideosyncracies in your drawing style that can easily give you away.
Or you just drop any collection of random factoids about you that, while each is probably harmless on its own, can form enough of a complete picture that people can go by process of elimination and identify you. Sure, there are lots of people who like [x] food, or watch [y] anime, or speak [abc] languages. But when you give away that you like all those things simultaneously, it narrows down the field dramatically to a few people who are only [x] and [y] and [abc]. If you already told the same stuff in your previous personas, people (either old fans who still remember that or new ones who just scour through all the cv's of every recently graduated vtuber) can connect the dots, either directly finding you or at least eliminating other possibilities who don't fit the profile.
And yeah of course, once you debut and people can actually hear your voice and see your mannerisms, it's basically game over anyway, because comparing voices is pretty easy and the biggest tell. Many vtubers are already found out beforehand because they made the errors above (and the voice reveal was just the final confirmation), but even the more opsec-minded talents that survive the pre-debut phase undiscovered will eventually get found sooner or later if they have any previous content out there on the internet.