Where is the Difference between Jaina and Sylvanas?



Easy!

Sylvanas is hostile towards the Alliance for no other Reason but secretely wanting to build up a second Scourge, while being protected by the Horde.



Jaina never threatened anyone, like Sylvanas threatened Gilneas for example,

yet she was still always met with Hostility from towards Orgrimmar. So the Difference is easy,

-> Sylvanas has no Reason to be pissed, but Jaina has. Sylvanas has no Reason to embrace evil and Revenge, but Jaina has.