I have two categories and one functor in each direction, with relatively long names. I would like to write both functors at the same time, one over a right arrow and another one over a left arrow, so it would be like, from top to bottom, text, left arrow, right arrow and text. It would be something like the first answer to this question How can I label \rightleftarrows above and below?, but more like \xrightarrow would show it, with its length growing to meet the text.
Any help would be appreciated. Thanks a lot!