I don’t see why you can’t carry one round as costume (even though you can hurt someone with it, you can do that with many things you find around anvil, just no one does) but it might not be such a good idea cracking it. If you are going to hitting against your hand while it is rolled up to intimidate someone then that may work but if you aren’t then you are going to have to think about space. The kind of places you are going to be trying to intimidate people in would probably small place, off to the side somewhere which mean you are more likely to accidently hit someone or something. When it gets dark, it will probably be a nightmare.
If your way of intimidation isn’t good enough, you are going to have to follow it up with something. That mean you would have to drop your whip and go for your weapon. That means they have time to go for theirs. You have to remember that most people at empire will not be afraid of threats of immediate violence as most people have chosen to do something combat related. If they think they can take you then they will go for it, the only thing slowing them down would be them wondering whether or not you can actually whip them.
There will be some people who you may be able to intimidate with it but they can always call for help and aid is probably sitting a few feet away or walking pasted. Also, they can use it to identify you afterwards.
Basically, do you actually want to try and use a whip other than for it’s look? I feel like it can only go badly.