Never say never but I very much doubt Kodi will be in the app store. The main issue Kodi has is support for Python. The ability to download and run code not blessed by Apple is a no no.
There is a fork of Kodi called MrMC in the app store now. But it doesn't support Python and therefore does not support any add ons.
So, if you want Kodi, sideload it. However, it is in pre Alpha stage now, and they are only focusing on the core of the app. Add ons may or may not work, and if they don't, then you'll have to wait months until Kodi on tvOS is in beta.
I tried the official PLP addon for Kodi, but it doesn't work on the ATV install