\documentclass{article}

\usepackage{commath}
\usepackage[math-style=ISO,bold-style=ISO,nabla=upright,partial=upright]{unicode-math}
\setmathfont{latinmodern-math.otf}
\setmathfont[range=\mathbb]{texgyretermes-math.otf}

\pagestyle{empty}

\begin{document}

\begin{equation*}
  \dpd{f}{x} = x^2
\end{equation*}

\end{document}

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%%% TeX-engine: xetex
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