I used the orginal Dragino Lora shield which used a Semtech SX1276/SX1278 chip with the hold microcontroller communicating via SPI - lora peer-to-peer communications used the lora.h library - if LoRaWAN was required the stack had to go in the host mico
the Dragino LA66 LoRaWAN Shield is based on the LA66 LoRaWAN module which includes the LoRaWAN stack with the host microcontroller communicating over serial using AT commands
don't know if the Dragino LA66 LoRaWAN supports LoRa peer-to-peer - certainly not using the lora.h library - have a read of the AT command documentation