\documentclass{article}
\usepackage[ngerman]{babel}
\usepackage[autostyle]{csquotes}
\pagestyle{empty}
\usepackage{demotext0}
%StartVisiblePreamble
\usepackage[usefilenames,
  RMstyle={Medium,Semibold},
  SSstyle={Medium,Semibold},
  TTstyle={Medium,Semibold}]{plex-otf}
%StopVisiblePreamble
\begin{document}
\blindtext
\end{document}
