Build config - netgear wndr3700 build to be used with rtl8812bu - 0bda b812

Hi everybody I'm new in here even if I've been using openwrt for long time.
I don't have too much time to spend in bad attempts (my 4 little kids hang around me all the day long...) so I apologise if I couldn't find the right answer by myself.

I'm trying to make work a wifi dongle, the drivers ara available and working, and could compile them for a raspberry.

I managed to compile an openwrt build (kernel 5.4), I wanted to take off the module from the build system and try to insert it in my router's kernel but then I realised that version 19.06.7 has kernel version 4.14.
If instead I checkout the 19.06 building system with kernel 4.14, the driver repository wont work because made for 5.4 kernel (and again I have no time to learn how to patch it).

My router is a netgear wndr3700 and this

is the repository to add kernel support to my dongle (using this I managed to complete the build process).

I would just like to find a working configuration file for my router to use, instead of making it from scratch thru menuconfig.

I've tried to look around but doesn't seem to be available.
Can U help me?

No special config is needed. Defaults for a device select proper packages.

Start with an empty .config and use menuconfig to select your device. That will set the needed normal packages.

Then select LuCI if you want GUI.

And select your own new kernel module.

and how do I determine for example the size of the image or other details (eg for my wndr3700 I need to choose if v1 or v2 and they differ only for flash size, so.. I miss the point..?)

The allowed image size gets set by the device.

You are expected to know which device you own.

In the v1 the label in the bottom of the router says just WNDR3700 while the v2 says WNDR3700v2


I know the model of my router.. maybe I've missed something, is there a place in the menuconfig where I can choose exactly my router model?

ok.. found..