For drones weighing fewer than 250g with no digital camera, neither ID is essential. That said, you still must comply with the UK’s drone legislation. According to the Drone Code, this means keeping Visible connection with your drone, flying no better than 120m higher than the bottom, staying a minimum https://www.aeroindustrial.com/product/dji-terra-upgrade-and-maintenance-fee-pro-overseas-permanent-1-device/