example_10.tex

\RequirePackage{luatex85}
\documentclass[tikz]{standalone}
\usetikzlibrary{arrows, arrows.meta, positioning,calc}
\usepackage{xcolor}

\definecolor{c1}{gray}{0.7}
\definecolor{c2}{gray}{0}

\usepackage{mptikz}
\begin{document}

\begin{tikzpicture}
	\tensorstyle{{len_vertical_legs = 0.4, tensor_width=1, tensor_height=1, trace_long='N', leg_style = 'line width = 0.5mm'}}
	
	\tensorstyle{{trace_offsetNS=0.2, trace_extensionNS=1}}
	
	\mpa{{1}}{{N=3, tensor_name='A1b', leg_color_NS='c1'}}
	
	\tensorstyle{{trace_offsetNS=0, trace_extensionNS=0}}
	
	\mpa{{1}}{{N=3, tensor_name='A1f', leg_color_NS='c2'}}
	
	\tlabel{'A1f'}{{ label='$A$' }}
	
	
	\draw[red, line width=0.4mm] ([yshift=-0.25mm]A1f_1_1_N3m) -- coordinate[midway] (t1) ++(0,0.3);
	\node[above right=0.5mm and -1mm, red] at (t1) {w};
	
	\draw[red, line width=0.4mm] ([xshift=-0.25mm]A1f_1_1_N3) -- coordinate[midway] (t2) ++(0.3,0);
	\node[above right=-0.9mm and 0.3mm, red] at (t2) {w'};
	
	
	\draw[red, line width=0.4mm]  (A1f_1_1_N2e) -- coordinate[midway] (t3) ++(0.2,0);
	\node[above right=-0.7mm and -0.5mm, red] at (t3) {a};
	
	\draw[>=latex, <->,red] (A1b_1_1_N1e) -- coordinate[midway] (t4) ++(0,1);
	\node[right= -0.7mm, red] at (t4) {e};
	
	\tensorstyle{{x=2.5, leg_W_mult=1.5, trace_long=''}}
	
	\mpa{{1}}{{N=3, tensor_name='A2b', leg_color_NS='c1', len_vertical_legs = 0.35}}
	
	\tensorstyle{{leg_W_mult=1.0}}
	
	\mpa{{1}}{{N=3, tensor_name='A2f', leg_color_NS='c2', len_vertical_legs = 0.25}}
	
	\tlabel{'A2f'}{{ label='$A$' }}
	
	\draw[>=latex, <->,blue] ([yshift=-0.3mm]A2b_1_1_N1e) -- ([yshift=-0.3mm]A2b_1_1_N3e);
	\draw[>=latex, <->,green] ([yshift=-0.3mm]A2f_1_1_N1e) -- ([yshift=-0.3mm]A2f_1_1_N3e);
\end{tikzpicture}

\end{document}