Handshake means new user (I believe 30 days or less). There are different reasons why to have a new account: new user, browser decided to finally get an account and post, people coming from other platforms (example: Voat). But shills and trolls also come in groups all at the same time. The handshake means nothing on itself. It is just a warning for the user: If a handshake account is posting all kind of dooming and fake news and crazy theories, he/she might be a part of an enemy trying to infiltrate, just be aware.