On sharelatex.com the Russian em dash works fine in document body, but does not work when used in macros. I tried to ask the support, they sent me here.
Code:
\documentclass[11pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T2A]{fontenc}
\usepackage[russian]{babel}
\pagestyle{empty}
\def\foo{
qwe "--- rty
}
\begin{document}
\foo
asd "--- fgh
\end{document}
Result: