With the Xbox controller, if I target a system in the GalMap it says '(HOLD) A OR (SPACE) to PLOT ROUTE', with A being the green Xbox controller A button.What sort of issues are you getting? I use a DS4 controller & Geforce Now to play Odyssey, in the Galaxy Map there was a bug in the "My Fleet" list which I reported to Sally on release day, but I hadn't noticed any other problems navigating around (yet). I'm launching through Steam with some custom button tweaks in Elite's own options screen.
If I hold A, nothing happens. I have to use space bar to plot routes in GalMap.