George here is another option. Using google enter exactly "Richmond Daily Dispatch/ Confederate Richmond - The Daily Dispatch"
When there enter the word treason
It will list all newspaper articles listing the word treason. I looked very briefly and saw a few men arrested for treason by the State of Virginia and South Carolina. I saw nothing by the Confederacy but it may have been so.
Yet another area to look into are the Gainesville, Texas hangings. This occurred on October 4, 1862. Some people have said this was the largest mass hangings in American History. As you are aware the first Confederate Conscription Act was in April of 1862. A rather large group of men refused to be conscripted. The newspaper article written well after the war said some were arrested for treason. It may have been so? But only your research will confirm or deny if it was treason and if it was.................did the State of Texas charge them or the Confederacy?
Once you have found the names of the men charged you can start doing more research. Fascinating area of research in my opinion.