Yes, this is possible.
To swap the rpm and frequency axes on a colormap display, right click in the display and choose “Options”.
In the “options” menu, click on the ‘Miscellaneous’ menu and choose “ZX” orientation rather than the default “XZ” orientation.
To make the axes swap the default, Click on the display name tab in the upper right corner and choose “Save as Layout” Press “OK” to overwrite the default ‘Colormap’ display.
Here are what the displays look like before (left) and after (right):