Output from HDMI Arc to both passive speakers and airplay speakers at the same time

[Tombiloo]

I would like to plug a WiiM amp into my tv using HDMI Arc and, if possible, output the sound to both my passive speakers and wireless (i.e. airplay) speakers. I do understand this is stereo but still think it might be good! If its not possible now, do you think this could be implemented sometime in the future or is it technically not possible?