Hi and welcome
We have a French section here at Wincert.
Yes, you can make an "universal" image by removing ei.cfg, it will then propose you the choice of the edition at the installation.
Here you can download French version of Windows 7: https://www.malekal.com/telecharger-iso-de-windows-7/#Windows_7_Edition_Integrale_x64
Then, you can use Simplix to update it with the latest KB: https://www.wincert.net/forum/topic/13434-simplix-update-pack-pour-windows-7-server-2008r2/
But be warned that Windows 7 is old now, you should move to Windows 10. The upgrade should be free from Windows 7.