Italics font in Emacs on Windows

[smartmic]

I have problems with the font (only) in Emacs on Windows 10.
If I install all 4 OTF font at once, Emacs will only recognize the Italics variant.
If I first install the Regular variant and in a second step the Italic fonts, the Regular (+Bold) font is shown in Emacs, but I cannot render Italics parallel to Regular.

Also, why are two font families shown in Windows Font Settings - one without version number (Regular, Regular-Bold), one with (Italics, Italics-Bold)?

[eigilnikolajsen]

Possibly an issue related to font naming.