The environment/sky being used currently is the Fast Stylized Procedural Sky.
what about the emote system?
The emote system and UI itself looks nearly identical to the Fortnite one, which AFAIK Unreal releases most of their assets from their games onto the epic games store.I should note that using assets not made by your team is by no means a bad thing. Even large AAA companies hire individual contractors for extra assets that are separate from the core team and if you were going to make the exact same thing anyway theres no point in wasting the effort when something else on the market does it.
the game's in a closed alpha and all you can do is build stuff as of right now, i'd wait until the game is actually in a developed state before you start calling it dead lol