They were a lot of stories that a Central-bank from one country or another banned Bitcoin.
What does it mean concretely after my interpretation ?
(I am not a lawyer but I have studies in economy and trading.)
The Central-bank is nowhere a legal or executive organ. That would be the parliament or at least the finance minister.
I could also say also that the USD is illegal or banned but it doesn't have any compulsory consequence for anybody.
So if anybody is trading or accepting Bitcoin in a country where the Central-bank banned it, he doesn't make any illegal action just because the Central-bank says so.

However to avoid problems:
- Why should somebody exchange in fiat if he has his prices in BTC ? He can keep in BTC and spend in BTC then the Central-bank is not competent for that use.
- If somebody needs fiat then should show the fiat prices and those who are buying with BTC can use something like Bitpay. Then there is again no problem. I am not sure if it exists something like Bitpay for specific local currencies.

What can happen in worst case that the Bank will not make the clearing for a trading to exchange in fiat or will suspend the involved account.
This decision is made based on the interpretation that the involved person made an unlicensed financial transactioin what is not necessary a valid interpretation of the local law and could be fought in a court.
As Bitcoin is not considered money accepting Bitcoin is just like barter trading which is not illegal. It is like you would exchange your horse for a cattle.