I recently had the Oreo update installed on my Nvidia Shield TV. I am running Kodi 17.6 on my Shield but I just discovered today new installed apps since the Oreo update are no longer showing up under Android apps under Kodi Addons. I am not sure if anyone has noticed this and if something changed with Oreo and how Kodi brings the app launcher into Kodi. The apps that were installed before Oreo are showing up available but just not the recently added apps.
Not sure if this is the same issue, but Read this thread...
https://forum.kodi.tv/showthread.php?tid=287826&page=98
from @
malte
Interesting. Just installed the oreo update last weekend, so I'll have a look into it. If you have any logs I can have a look. (enabled logging in AEL too)
RCB users reported the same issue with Android 8. Seems like invoking apps via "system/bin/am" has been limited due to security reasons. Until now I did not find a way to solve this. If you find anything I would also be glad to know. Arc browser is reported to be still working with Android 8. But afaik this is a native Android app, so maybe it has other options to invoke the emulators.
It maybe only sideloaded apps that Kodi doesn't make available.