I am not sure if I understand what you want to do. But I think a solution would depend on the class and the package used for page header and footer.
Maybe you can use package scrwfile
to clone the ToC in a new list and tocbasic
to formate the entries in this new list.
Example:
\documentclass{book}
\usepackage{scrwfile}
\TOCclone[Running heads]{toc}{lorh}
\AtEndDocument{\listoflorh}
\usepackage{tocbasic}
\makeatletter
\AfterTOCHead[lorh]{
\let\MakeUppercase\relax
\value{tocdepth}=0
\pagestyle{plain}
\DeclareTOCStyleEntry[
pagenumberbox=\@gobble,
entryformat=\bfseries\Large
]{tocline}{chapter}%
}
\makeatother
\DeclareTOCStyleEntry[
indent=0pt,
beforeskip=3pt,
level=0,
numwidth=0pt
]{tocline}{rhverso}
\DeclareTOCStyleEntry[
indent=5.5cm,
beforeskip=3pt,
level=0,
numwidth=0pt
]{tocline}{rhrecto}
\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\sectionmark}[1]{}
\renewcommand{\subsectionmark}[1]{\markright{\thesubsection. \MakeUppercase{#1}}}
\fancyhead{}
\fancyhead[LE]{\leftmark\addcontentsline{lorh}{rhverso}{\parbox[b]{5cm}{\protect\raggedright\leftmark}}}
\fancyhead[RO]{\rightmark\addcontentsline{lorh}{rhrecto}{\parbox[b]{5cm}{\protect\raggedright\rightmark}}}
\usepackage{blindtext}% only for dummy text
\begin{document}
\tableofcontents
\blinddocument
\blinddocument
\end{document}
or with scrlayer-scrpage
instead fancyhdr
:
\documentclass{book}
\usepackage{scrwfile}
\TOCclone[Running heads]{toc}{lorh}
\AtEndDocument{\listoflorh}
\usepackage{tocbasic}
\makeatletter
\AfterTOCHead[lorh]{
\let\MakeUppercase\relax
\value{tocdepth}=0
\DeclareTOCStyleEntry[
pagenumberbox=\@gobble,
entryformat=\bfseries\Large
]{tocline}{chapter}%
}
\makeatother
\DeclareTOCStyleEntry[
indent=0pt,
beforeskip=5pt,
level=0,
numwidth=0pt
]{tocline}{rhverso}
\DeclareTOCStyleEntry[
indent=5.5cm,
beforeskip=5pt,
level=0,
numwidth=0pt
]{tocline}{rhrecto}
\usepackage{scrlayer-scrpage}
\automark[subsection]{chapter}
\ihead{%
\headmark
\ifodd\value{page}%
\addcontentsline{lorh}{rhrecto}{\parbox[b]{5cm}{\protect\raggedright\headmark}}%
\else
\addcontentsline{lorh}{rhverso}{\parbox[b]{5cm}{\protect\raggedright\headmark}}%
\fi
}
\usepackage{blindtext}% only for dummy text
\begin{document}
\tableofcontents
\blinddocument
\blinddocument
\end{document}