Is your feature request related to a problem? Please describe.
Usually ports, AFAICT, are built with /Z7 which also makes debug symbols available when building static libraries. The botan port is built with /Zi /FS instead.

Proposed solution
I'm not sure whether it's possible to change this option with the provided configure.py. Otherwise the compiler info in src\build-data\cc\msvc.txt must be patched.