Is it possible to select multiple elements in the Chrome Developer Tools Elements panel?

The answer is NO, it is not possible to select more than one element at a time in the Chrome Dev-Tools. You may refer to the Chrome Dev-Tools Tips and Tricks https://developer.chrome.com/devtools/docs/tips-and-tricks

Go to the parent that contains all of the html elements that you want to influence ... edit as html. Then you can modify everything inside however you want!