% Use standalone to generate PDF images
	% Recommended in slower machines and big files!
\documentclass{standalone}

	% Standard LaTeX libs
\usepackage{mathrsfs}

	% TikZ
\usepackage{tikz-cd}

	% Enable if using Overleaf to speed up compialtion times
	%\usepgfplotslibrary{external}
	%\tikzexternalize

\begin{document}
\begin{tikzcd}
                                                          & \mathscr{F}_x                                                   &                                            \\
	\mathscr{F}(U) \arrow[rr] \arrow[d,"\phi"] \arrow[ru] &                                                                 & \mathscr{F}(V) \arrow[d,"\phi"] \arrow[lu] \\
	\mathscr{G}(U) \arrow[rr] \arrow[rd]                  &                                                                 & \mathscr{G}(V) \arrow[ld]                  \\
                                                          & \mathscr{G}_x \arrow[dashed, from=uuu, crossing over, "\phi_x"] &
\end{tikzcd}
\end{document}