When linking against gpgmepp, it's impossible to call gpgme_set_global_flag directly; and this prevents e.g. setting correct gpgme spawn executable path on Windows. The problem arose in LibreOffice (see [1], and commit [2]).
I had prepared a PR to old github.com/KDE/gpgmepp [3]. I realize that it's correct that it's closed, so hopefully I do it right this time.
[1] https://lists.freedesktop.org/archives/libreoffice/2019-April/082534.html
[2] https://git.libreoffice.org/core/+/cca6830288f8d4f541077ead5ee229e02304601d
[3] https://github.com/KDE/gpgmepp/pull/1