I saw this bike made by an independent bike shop for himself.
It’s an electric longtail and can carry a 300kg europallet, plus the toolbox on the front, plus an extra person or material on the bike rack!
Here is the link to the shop website: https://www.cycles-penet.fr/
The one good part is if the trailer overbrakes it self releases as the pressure comes off the actuators. I towed a fully loaded trailer with those brakes across Canada ( through the mountains ) and you didn’t even know it was back there.