I had a similar idea a while ago leaning towards development with others. I can say that UE4 will easily handle what it is your trying to accomplish. VOIP is almost a standard feature if it isn’t already so I’m betting the functionality is here, you just need to look into how to tap into it. Look up VOIP and other network/internet functionality. As far as content goes, your get what you put in. If you don’t want kids to see something, don’t put it in! Not sure how the online chatting “censor” stuff works though. That might take some Blueprinting with a library look up table kind of thing.