\definefontfeature[smallcaps][mode=node,smcp=yes,script=latn]

\definealternativestyle[TitleFontStyle][{\switchtobodyfont[50pt]\addff{smallcaps}}]



\setuphead[title][style=TitleFontStyle]

%\tracingall
\starttext


\title{A Title Test}

Hello there {\setff{smallcaps}capped 123 \setff{oldstyle}123!}

\stoptext