I figured out how to tell the difference between bots and real players pre lobby screen. Bots will do emotes and you cant mimic them. You can only mimic real players emotes.
EXPOSING* Epic Games - The TRUTH about BOTS! - YouTube
How To Get Bot Lobbies In Fortnite Without Another Account - BrightChamps Blog
Matchmaking, Bots, Controls, and The Combine Update
I tried to get a BOT a Fortnite win and then this happened... - YouTube
Fortnite News on Twitter: "Look familiar? We've seen this same exact skin combination in our lobbies, as well. #FortniteSeason3 bots have chosen their uniform. Via: u/whombst_was_fone https://t.co/tSfakGJwUS" / Twitter
🎮 Fortnite Bots | Are bots coming to Fortnite? | Lurkit