Since no one seems to know, this is a feature of spectator mode on java edition.
It has nothing to do with hypixel or otherwise, it’s a feature of minecraft itself
That would be Simply Cubed from the Minecraft marketplace, however for future reference, if you have off-topic questions like that you can always message the individual
this would be hard to do and mojang may be needed to tweak things for this. I Do believe the spectator could be constantly moved when the player moves but that would be laggy
The typical way to do it , using commands, only happens 20 times per second. It has a noticeable stutter if the player is moving quickly in any direction. I doubt that Hive would use commands for a feature like this though.