You can certainly build a Mesh network on top of raw LoRa - I was still at Pycom when development started around their OpenThread based LoRa Mesh implementation - or you can build a simplified version like the Nooropic Design you shared.
LoRaWAN however is a different beast, a gateway must be ready to issue downlinks at very specific time windows - and have the duty cycle to meet them - and you want to optimise the amount of time it is listening on air. So while you could build it the performance would be very poor. This is why I said it you cannot be operating both roles at the same time and expect to be good at either of them.
I actually doubt the Lemberg Solutions you shared is genuine as it’s marketing text very light on details on the mesh side and full of errors/misleading claims on the non-mesh parts of the text (“A single CR coin lithium battery enables a class C LoRa chipset to work for at least a year” - that must be some giant CR battery!)
What the LoRa Alliance has been working on for some time is an ability to use LoRa as the gateway backhaul, but this will very likely necessitate different hardware (separate TX and RX antennas for example)