Hi, @Sapte,
yes, you got the point. Italian public administration is... "famous" for make hader the simple things :-)
I leave here some points, just for reference:
1)
At this url you can find an useful editor for radio patterns: https://www.wireless-planning.com/antenna-pattern-editor
including a good database of msi files.
2) msi (and other radio patterns files) files are usually for mobile phones and public data connections, not for wi-fi ones.
3) Huawei actually DO provide msi files to its partners, like the one I work for, and I have got what I was looking for (in a matter of 1 month :-( that's the point)
let me know if I'm allowed to share the files.
Thank you all.