Since GJ cannot ally with anyone but Gallic lawfuls, I believe SJ and GJ are at least neutral to themselves, if not unfriendly.
However, I believe neutrality would be the best solution, since GJ and SJ would technically ally against Hogosha and Unione Corse, yet Gallic Junkers in presence of GRN would turn on Junker claiming Gallic lawful's head - or just leave, left to the player choice. Or Junker would turn against Gallic Junker, if Outcasts are around.