The #1 suggestion that people facing this type of issue get is to wire their core. If it were me, I’d purchase a $20 dumb GB switch and be done with that.
There are a number of threads on this, but it’s a strong Roon suggestion to wire your core at a minimum. Id certainly wire one of your Sonos endpoints as well. I realize it’s not what you want to hear, but Roon is very very demanding network wise. Good luck.