An app that is critical for Android TV and suggested to Kodi for Android users is Multilanguage Keymap Redefiner which allows keypress code remapping. It is a free utility that is simple and basic but the author has stopped development (I suspect due to the headaches of security updates in newer Android versions). I reached out to the email address provided, asking him to release the source so development can continue but never received a response. Maybe others can persuade him or recreate from scratch.