\setupbodyfont[pagella,11pt]

%\setupMPinstance[metafun][textstyle=sans]
\setupMPinstance[metafun][textstyle={\switchtobodyfont[termes,14pt]}]

\starttext

\input knuth

\startMPcode
draw textext("I’m different!") ;
\stopMPcode

\stoptext

 
 
It gives an error:
 
! Undefined control sequence.
system          > tex > error on line 1 in file GeneraMapa.tex: Undefined control sequence ...
1 >>  \setupMPinstance[metafun][textstyle={\switchtobodyfont[termes,14pt]}]
2    
3     \setuppagenumbering[location=]
4     \starttext
5     \input ./mapa.tex
6     \useMPgraphic{mapa}
7     \stoptext
8    
l.1 \setupMPinstance
                    [metafun][textstyle={\switchtobodyfont[termes,14pt]}]
?