Hi,
I would like to know if it would be possible to make the GL-E750V2 Mudi show a Wifi connection barcode on it's oled screen. A data matrix code can be rectangular and given that the screen is likely a 128*64 pixel one, it should be capable of handling that.
You can already choose to show the SSID and Password bit to just scan the code would be really convenient.
And which device should read it then? No normal device (even phones) will read data matrix to get the Wi-Fi credentials... 
Ok, QR-Code, then. A 2929 module QR code can store 77 alphanumeric characters, should be enough for most people.
Using modules a size of 22 pixels should be easily readable. 6161 Modules with 11 pixel per module would store 468 alphanumeric characters, more than enough. A size like this could be tested if common phones would be able to read it.