If a font doesn't contain a specific face, it is substituted by default face (like \mdseries), while I want to define a chain of fallbacks, so LaTeX keeps searching for an existing face, until it succeeds, e. g.
black -> extrabold -> bold -> regular.
How can I do that?
My MWE
\documentclass{article}
\usepackage{fontspec}
\newfontfamily{\Warnock}{WarnockPro}
\newfontfamily{\Vollkorn}{Vollkorn}[
FontFace = {black}{n}{*-Black},
]
\begin{document}
\fontseries{black}\selectfont
\Vollkorn Hello
\Warnock World
\end{document}