UK EV drivers using medical cannabis should be aware of the ‘in charge’ rules....

https://evpowered.co.uk/feature/electric-vehicles-and-medical-cannabis-what-uk-drivers-need-to-know-about-the-law/

UK EV drivers using medical cannabis should be aware of the ‘in charge’ rules. Even while parked and charging, the 2 micrograms per litre THC limit applies