Just switching the keys around won’t do you much good. It would put the letters in the right place, but US Qwerty and Azerty have different combinations of punctuation on different keys as well. So some (shift-)symbols would still be in the wrong place, even if you switched the plastic keycaps.
The only “real” solution is what CrumblePie suggsted: Put the input language/keyboard in Windows itself to Azerty and type blindly, or as you already suggested put the right sticker-pack on.
Of course there’s another solution: Just use Qwerty
It took me a while, but I’ve been typing Qwerty in an Azerty-country for years, and the advantages are numerous: Cheaper laptops, cheaper keyboard and a more flexible brain. I type DVORAK on my main computer, use Qwerty on my mobile devices (like the Chuwi’s) and seamlessly switch to Azerty when configuring one of the kid’s computers.