Quectel RG520N-EU driver for Ubuntu 22.04 (kernel 6.5.0-28-generic)?

The Linux kernel driver include 2 parts.
For usbserial please it is the option driver. The source code is in the Linux kernel and you just need to add the VID & PID into the option_ids.
For the usbnet, you can try the qmi_wwan_q I just sent.