\setupbodyfont[dejavu]

\definemarking[country]

\startsetups myheader
    (\getmarking[country][1][top]\enspace\emdash\enspace\getmarking[country][1][bottom])
    \hfill
    (\getmarking[country][2][top]\enspace\emdash\enspace\getmarking[country][2][bottom])
\stopsetups

\setupheadertexts
  [\setups{myheader}][]
  [][\setups{myheader}]

\def\anothersection#1%
  {\par
   \dontleavehmode
   \marking[country]{#1}%
   \start\bf #1 \endgraf\stop
   \quad
   test
   \par}

% \enabledirectives[marks.boxestoo]

\starttext
    \startmixedcolumns[distance=5mm, balance=yes]
        \anothersection{Brazil}
       %\anothersection{Suriname}
       %\anothersection{Uruguay}
       %\anothersection{Bolivia}
       %\anothersection{Venezuela}
        \anothersection{Peru}
    \stopmixedcolumns
\stoptext

