I am new to using the ORS plug-in through QGIS and ran into this same issue. The solution makes sense, but how do I change the preference parameter for matrix queries in the QGIS plug-in? I don’t see it in the “ORS Tools” toolbox; the main form allows selection of “Travel mode” only, and the advanced options (“Algorithm Settings”) don’t seem to support that preference change either. There is a preference option in the menu (accessed via “Web” → “ORS Tools” → “ORS Tools”), but as far as I can tell that only impacts the waypoint navigation function - not the matrix function in the toolbox.
I might be missing something obvious, so any guidance would be greatly appreciated!