For drones weighing lower than 250g and not using a digicam, neither ID is necessary. That said, you still must comply with the UK’s drone legislation. According to the Drone Code, This suggests keeping Visible contact with your drone, traveling no greater than 120m higher than the ground, being at https://www.aeroindustrial.com/product/dji-matrice-3d-con-dji-care-plus-1-ano/