Back when i started doing scratch i was allways trying to make the perfect cloud engine, but allways failed, they we're all to inefficient. Now, around 3 years later, I got to the point of seeing how rosty my coding skills are, and, turns out, I managed it to actually code an pretty good one. in the encoded list (its so small because scratch sometimes is buggy im maybe gonna fix it), you can allways see a list of the usernames using the project and an unique tick id right below them. In an multiplayer game, you would also send, for example x and y coordinates, which would then also be added to the encoded list, so you could take them out of there and render players. i didnt do that because i was to lazy lol if you got any questions, ask them Spoiler: im not actually sure if it works, i shall do some testing, but i just trust my skillz.
thanks to my idol back then, @cloud-multiplayer