If the frame is not an ultra-light, high-end model, then it should be robust enough for hauling a BOB. There are no guarantees but 'dales are tough, strong frames. With a trailer, you dont need touring grade wheels, the luggage weight is supported by the trailer.
Gradients in the UK can be steep and in France the climbs can be are long, so you will need some low gears. A triple may be called for. You dont need to get high end stuff for a one-off tour.