Royal: Top zoning tools. This is the variation that doesn't need a lot of work, just a fix on move startups and recovery frames to make her more nimble and capitalise on her mobility. Fans should hit mid, but I wouldn't mind fans in Royal Storm being an overhead at the cost of losing her Neck Slice.
Assassin: Punish and footsies at the cost of losing her fan lift move and focusing on high damage with slice and dice moves and Sharpen. Bringing back her Fan Slice and making it a Mid with pushback on block would be an idea. Make assassin dash airborne, too.
Just my quick brain(royal)-storm.
Fans being overhead sounds like it's a bit too much to be honest on Royal. I mean I realize that she doesn't have mix ups, but it seems a bit dirty to give her that...well not super bad but pretty bad. For Royal, I'd reduce the start up of Bounce back, making it a more viable tool in a zoning war. Fans being mid would cause the opponents to take more risks, giving her more opportunities to actually punish more moves, and the opponent will be more likely to jump. Though good players will still get to her by blocking and running. I'd increase the length of the super booty. Meaning it would go further, but I'd keep it's recovery frames the same to keep it from being spammable/get out of jail free.
Assassin: I'd reduce the recovery of fan sharpen (the thing has over a second in game time recovery), fans hitting mid still sounds good, I'd reduce the start up of parry probably to 5 frames. It only hit's overheads/mids and doesn't hit jump ins or low. Making it a pretty useless move. I'd Increase Assassin Strike's armor count as the final specific buff.
As for universal changes, reduced recovery on almost all of her strings. Being full combo punishable on so much is pretty dumb. F2 can keep it's full combo punishableness from even a basically slow string. But make it an over head. A 19 start up overhead in a game with this many mix ups isn't bad at all, It also scales combos considerably.
And that's probably all my changes to be honest. Nothing game breaking. I don't think it would even make her top tier, but it would make her a better character in the long run.