Q. Massive Online Multiplayer.

I can’t find answer about max client numbers for UE4. (I need over that 64 clients, 1000 or bigger) Where i can read about it ?

UT4? You meant UE4, didn’t you?

UE4 was not designed with MMO games in mind.
I believe you’re able to overcome the 64 clients limit, but you’ll face huge bandwidth problems. You’ll have to write your own custom server solution to have massive multiplayer support, which includes spreading clients over different server and then synching when needed and everything else that is used in MMO games. Network relevancy will help greatly here, but will not solve this completely. I believe there was some thread about MMO servers around, let me find it.

Edit: Found few topics covering your question.

Thx. Yes , UE4 ))not UT4