If it is in front of the wheel well and you are tall enough or have a step you can stand on you can lean over the bed rail and plug the cord in with the trailer attached. But being that far forward, it could possibly interfere with things you may load in the bed in front of or beside the hitch.
Behind the wheel well as mine is, I don't have enough space to get my head between the 5er overhang and the bed rail. So I have to lean around over the lowered tailgate to plug in. But I can reach it fairly easily. Still some possible issue with something in the bed. But I have carried a child's bike laying in the bed behind the hitch several times and no problem with the cord. Mine was installed behind the wheel well near the tailgate by the factory.