I have this setup and wanted to know if its possible to use both my HomePod and my Samsung Soundbar 2.1 speakers simultaneously to listen to music, watch YouTube, TV shows, Movies, Plex, etc?
Long answer - you could if you got creative and played everything through a mac/iDevice/tv and attach that soundbar to an Airport Express and use it as an AirPlay speaker. Alternatively you could trade your Samsung bar for a sonos bar with AirPlay 2 but you'd still need something to interface with AirPlay 2.