In meiner cls-Datei habe ich folgende Einstellung:
\RequirePackage [natbib=true, citestyle=authoryear-comp, backend=biber, autocite=inline]{biblatex}
\RequirePackage{csquotes}
\RequirePackage [natbib=true, citestyle=authoryear-comp, backend=biber, autocite=inline]{biblatex}
\RequirePackage{csquotes}
\if@langgerman
\RequirePackage[main=ngerman,english]{babel}
\babeltags{lang-main = ngerman}
\else
\RequirePackage[main=english,ngerman]{babel}
\babeltags{lang-main = English}
\fi
\babeltags{lang-de = ngerman}
\babeltags{lang-en = English}
\RequirePackage[T1]{fontenc}
\RequirePackage [natbib=true, style=authoryear-comp, backend=biber, autocite=inline]{biblatex}
\DeclareLanguageMapping{english}{english-apa}
\RequirePackage{csquotes}
\parencite*[cf.][]{key}

