Venus was NEVER a greenhouse planet. There is very little free water in its atmosphere, and the average atmospheric temperature is over 900 degrees Fahrenheit, at which point water dissociates, creating free hydrogen, while the oxygen is taken up by various sulfur compounds, and the hydrogen quickly recombines into other substances or escapes to space altogether.
There may be enough of both hydrogen and oxygen to combine into a decent supply of water, once the planet cools enough, but until the heat is radiated off by some means, Venus is forever a stillborn twin of earth. The “cloud cover” is largely sulfuric acid, and most of the atmosphere is carbon dioxide.
You want a REAL “climate change project”? Terraform Venus.
Wouldn't our Lib "friends" say it was our ancestors that ruined Venus and escaped to earth? I know some lunatic left-wingnuts who would probably say that!