https://www.yosepower.co.uk/collections/e-bike-accessories/products/brake-sensor-only-for-shimano-mt200-brake
If you have Shimano MT200 levers , you also have the above option. I've had mine for a few weeks and they work okay but I can only compare with the wuxing cable levers on another conversion.
Does anyone know the make/model of the bike second from the left (rear rack, smallish rear hub motor?) and/or what's likely to be illegal with that?
I can only think throttle-only rather than PAS or perhaps the label or lack of label.