>>11389947You have to remember that those figures are slightly screwed up by the fact that venus has 90 times the amount of gas present in Earth's atmosphere. So while Venus' atmosphere is definitely majority CO2, if you froze that, the remaining ~1% Nitrogen content would be roughly comparable to the amount of Nitrogen we already have on Earth.
If you get a little Oxygen separation going on with all that CO2 you should end up with a pretty manageable atmosphere similar to our own, same density, roughly same mass, and hopefully same ratios of gasses.
The only problem I could see that would be an ongoing challenge is creating some form of ocean on Venus for Plate Tectonics and to help trap the CO2, as well as helping with climate regulation. While we have an idea of what caused Venus' greenhouse effect to go runaway, we still wouldn't know if we might repeat that process by accident if we introduced a significant amount of H2O to the planet.
Even then though, we still have two major problems that would undo everything we're working for; Venus' rotation and core. Venus has one of the longest rotational periods in the solar system-- it orbits the sun in a shorter time than it rotates, and even then it rotates backwards compared to earth! How do you speed up a planet's rotation? Give it a moon? Impact it hard enough that it starts spinning? Either choice isn't pretty. On the other hand though, you probably could employ the use of some sort of massive solar shade that rotates around the planet once every 24 hours. Sure, you wouldn't exactly solve the issue of the planet's slow rotation, but you'd fix it enough for it not to be a huge problem.
The core though, is a big problem. Without an active core like Earth, Venus' atmosphere, even today, is slowly being leached away by Solar Wind. Not only that, but the increased amount of radiation not being blocked off by the sun means anyone living on this Terra formed Venus would have to live in lead lined containers.
