Certified GKH Gardening Expert
If they are in containers, you can easily move them to a shadier location. Unless you acclimate them, they may suffer from stress in the basement, going from one extreme to another, but if the temps are reasonably close to what they normally receive outdoors, this should be okay. You can also get some shade cloth for plants that cannot be moved. Also, make sure they are receiving plenty of water during heat waves/drought.