H-shaped diagram with Tikz-Feynman

Question

I am new on Tikz-Feynman and I am trying to write all possible diagrams that I have studied. Currently, I am working on this diagram that comes from an effective field theory: the output are two straight and parallel lines, that exchange two other straight and parallel lines. I would like to insert another propagator in the middle but perpendicular, in order to have a H-shaped diagram, how can I do this? This is my code

\begin{equation}
\centering
\feynmandiagram[medium, layered layout, horizontal=a to b] {
i1 [particle]--  a-- b-- f1,
i2 [particle]--  c--  d-- f2 [particle],
{ [  same layer] a -- c },
{ [  same layer] b -- d},
};
\end{equation}

Answer 1

You can get the perpendicular line by adding a third row in the middle and leaving the incoming and outgoing particle lines undrawn for that row:

\begin{equation}
\centering
\feynmandiagram[medium, horizontal=a to b] {
i1 [particle]--  a -- b -- f1 [particle],
i3 --[draw=none]  c --  d --[draw=none] f3,
i2 [particle]--  e --  f -- f2 [particle],
a -- c -- e,
b -- d -- f,
};
\end{equation}