I am looking for the transport from Wutai Shan to Pingyao on July 30th for 1 person.

There is usually one pair of normal speed trains running between Wutaishan and Pingyao, with duration of about 5 hours. If you want to visit Wutaishan on July 30th, I suggest you can take the only train from 00:05 to 04:49 on July 31th, and you can have a short rest on train. When you arrive, you can also find a hotel nearby for rest. Then you can visit Pingyao in the daytime.