Unreal Engine or Unity for 10,000 online?

Question

Game development

The essence of the question is which game engine to choose for an MMO project where a fixed amount of online is 10,000.
While working with this question, I have never encountered it, and if I ask my colleagues, it will be very suspicious.
What all the same to choose and where there will be fewer pitfalls and the best solution for implementation?
Help!)

Answer 1

Not a single engine will pull 10k, moreover, not a single client hardware will pull such a number of people online, so on the backend the world is divided into regions and they are not allowed to meet everyone in one place.
True, there are moments when hundreds (TOTAL!) of active players are gathered in one place in the world, and then everyone starts having problems.
Eve online have filed their own engine and only they seem to have no special restrictions on this (except for the notorious time dilation).