PVK

It is available at US store: https://us.lgappstv.com/main/tvapp#  with the following description: Oneplayer is a multi-platform player for playing m3u playlists in a common format, suitable for playing audio, video, radio, live playlists. It is mainly intended for Internet TV playlists. For this, support for categories, program guide, archive and timeshift is built-in. The application does not contain video and audio content, but is intended for playback. The app is designed for Russian speakers around the world.

I can niether stream my videos on my PC to my LG TV. LG does not have an app in their app store. I am therefore using PLEX. However Plex won't detect MKV files, You could try this solution: https://www.easefab.com/mkv-tips/plex-cant-play-mkv-solved.html

I cannot see SmartShare on my LG oled tv OLED48C16LA