FYI, I've been playing with ethernet bridging behind a wifi client with vxlan. With a relatively recent kernel you can make that work using vxlan and nothing else.
The repo here has files for raspbian, but nothing is raspbian/pi specific, really: https://github.com/epoch1970/a-bridge-too-far
I tested audio sync between a few SBs segregrated behind wireless clients, including one SB3, and it works fine as long as wifi signal strength is correct.
Also the LMS server needs its own network interface MTU set to 1450 or an SB3 will not work. (Post)
I don't think using wifi as a backhaul link is a good idea, but if that's the only practical possibility or if you want to put over wifi a player that is ethernet only, this is a practical solution that won't break the bank.
HTH
The repo here has files for raspbian, but nothing is raspbian/pi specific, really: https://github.com/epoch1970/a-bridge-too-far
I tested audio sync between a few SBs segregrated behind wireless clients, including one SB3, and it works fine as long as wifi signal strength is correct.
Also the LMS server needs its own network interface MTU set to 1450 or an SB3 will not work. (Post)
I don't think using wifi as a backhaul link is a good idea, but if that's the only practical possibility or if you want to put over wifi a player that is ethernet only, this is a practical solution that won't break the bank.
HTH