\setuplist
  [section]
  [alternative=MyListItem,
   after=\blank,
   before=\blank]

\definelistplacement[MyListItem][command]#1#2#3{(#1) (#2) (#3)\par}

\definecombinedlist[whatever][chapter,section]

\starttext

    \placecombinedlist[whatever]

    \chapter{test}

    \section{test}

\stoptext
