Edit:
Well i ve followed this guide and managed to use my xbox controller with moonlight embedded (didnt use the kodi-add-on). It works as expected and thanks for this nice how to!
About kodi-addon: Nice RGUI and very nice try really. Of course there are problems too. One major one is in having any of my controllers to work. This is my add-on settings. I always get a “input device not mapped” even though there is an xbox controller in /dev/input/eventX found in lsinput command. My keyboard/mouse inputs are working as expected. So for now - i leave it aside 
Now - the only think that remains - is how to use my second/3rd wired controller with moonlight embedded! If anyone knows please share it with us!