Transfer edges are commonly used in a network dataset to carry a time cost in one direction only (either to-from or from-to). This is fine if the impedance used is time, i.e. find the route that will take the shortest time. However, if the impedance is now set to distance (find the shortest route), will the length of the transfer edges unfairly impact the length of the route?
How do you mean "unfairly"? The solve will take into account a distance field that you set as an evaluator. You could use Shape_Length for the actual length of the edge, or you could create your own field that has some other distance attribute and set the evaluator to that.