Wyze has millions of active cameras with thousands using cameras outside. Exterior walls are usually thicker. You could put a wifi access point closer to the camera. Also many users vouch for poe access to the camera to eliminate the need for wifi. You can vote here.
Also I’d update your WIFI router if haven’t already.
I just bought a MESH system and it’s WIFI transmition is awesome from end to end … from corner to corner of our probrety.
Since you did not specify in details the setup of your WiFi network, I hope you don’t mind if we verify what’s brand/model of the WiFi router you’re using? is it dual/tri band? did you configure a separate SSID for the cameras under 2.4G band?
On the mesh it also helps to do the setup with the cam close to the mesh satellite that u want it to connect to.
Sometimes it want to connect to the main ,which is farther away.
Then move the cam to the spot u had placed it.