\AtBeginSubsection{\begin{frame}{\bititle\\Plan}
\begin{columns}[t]\begin{column}
{.5\textwidth}{\LARGE Mémoire}\vspace{1em}
\tableofcontents[currentsection,currentsubsection,
sections={1-2}]\end{column}\begin{column}
{.5\textwidth}{\LARGE Présentation}\vspace{1em}
\tableofcontents[currentsection,currentsubsection,
sections={3-4}]\end{column}
\end{columns}\end{frame}}
%–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
\begin{document}\maketitle
%–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
\begin{frame}{\bititle\\Plan}
\begin{columns}[t]\begin{column}
{.5\textwidth}{\LARGE Mémoire}\vspace{1em}
\tableofcontents[sections={1-2}]\end{column}\begin{column}
{.5\textwidth}{\LARGE Présentation}\vspace{1em}
\tableofcontents[sections={3-4}]\end{column}
\end{columns}\end{frame}