The precise way to perform this protection would be to install two different protections: one for the short line and another to the power transformer. But presently an overall solution already exists. One manufacturer is employing this solution in a plant I am working now. A conception of IEDs is adopted and a line differential is located in the substation and connected to the local currrent transformers. A fiber optic is deployed between the substation and the power transformer. The power transformer has a secondary BCTs set connected to a regular differential relay and the primary to HV BCTs set, The fiber optics is connected to this differential transformer and the line will be protected and the power transformer as well