\input{umtest-preamble}
\usepackage{unicode-math}
\setmathfont{STIXGeneral}
\begin{document}
\[ \mathbb{πΠγΓ} \qquad \mathbb{𝜋𝛱𝛾𝛤} \]
\[ \mathbb{\sum}_0^1 \]
\[ \mathbb{∑}_0^1 \]
\[ \Bbbsum_0^1 \]
\end{document}