With the recent news that Sonos appears to be launching their own voice assistant, I would guess the chance that Yandex Alisa assistant will be added to Sonos is pretty low:
https://www.digitaltrends.com/home-theater/sonos-voice-control-google-assistant-amazon-alexa/
If Sonos would ban GA from it’s speakers I would be very disappointed, since Alexa is not available in my native language. This would be a step back……..
I do not know how it would work for Yandex to get their assistant onto Sonos, but I understand that if you would want you music service added by Sonos you need to contact them. @Cr0ss Did you ask Yandex?
The music service is already there, the only think that we all are dreaming about is voice assistant.
and maybe Apple spatial audio thru Sonos app :)