Hello,
a friend and I installed a debian testing from the iso available here:
https://cdimage.debian.org/cdimage/daily-builds/daily/arch-latest/amd64/iso-cd/
When you choose French, and install the mate desktop, the graphical
interface is in English, while the rest of the system is in French.
however, the keyboard is in azerty as I requested during installation
If it's any help, I'd like to point out that the first test was carried
out on December 9 and my test on December 15, and the bug is still present.
thanks,
Jerem