The only change in Unioners political infocard is Corsairs being allied with Unioners is now replaced with Bundshuh. And Bundshuh are hostile with Corsairs so thats why now it will be disputable to use Corsair weapons for Unioners..
EDIT: Well Unioners will stay as neutral in the OC vs Corsair war this is for sure and they are already limited in Rheinland territory so they would not be able to interfere in any way. The changing thing is we will not be hostile against Bundshuh, Hessians, Hackers, Rogues, Outcasts, Blood Dragons in any way..