My house faces south, and the neighbors on the left connect the old alleys. Is it good for feng shui on the right?

Okay, there's nothing wrong with this. The question you asked has nothing to do with Feng Shui. There is no distinction between good and bad. In fact, there are not many things related to Feng Shui in real life. Not everything is related to feng shui. Don't associate everything with feng shui.