For drones weighing below 250g and not using a camera, neither ID is necessary. That said, you still should adjust to the UK’s drone regulations. According to the Drone Code, This implies keeping visual contact with your drone, flying no larger than 120m higher than the ground, keeping a minimum https://www.aeroindustrial.com/product/dji-matrice-3d-con-dji-care-plus-1-ano/