How to make a full backup that also works on android and LibreELEC

I configured Kodi to my personal likings with custom backgrounds and menu’s on my Macbook and would like to transfer everything to other devices like my android box and another box running LibreELEC. I first tried this using the Backup add-on from the official Kodi repo, it copied my skin and add-ons like trakt, but didn’t copy my custom menu’s and backgrounds. Then I tried another method, unaware that it is not supported by the Kodi community, whoops. Since those 2 didn’t work out I’m curious if there’s a fool proof method to transfer a full backup between devices running the same Kodi version but different operating systems, or am I dreaming and will I have to go trough all those steps with my android tv box remote?