Of course the price will immediately rise, if it has been accepted by all countries, even at this time perhaps large companies are preparing to buy if regulations regarding BTC or news about BTC goes well.But it's just a matter of time.
Immediately ? there is no way it will happen overnight because we knew that market will react depending
to how much each country invest and uses.
and not just because it is accepted meaning the whole country will comply that great.
Each country has its own rules and regulations, so the application of Bitcoin in each country will be different even though they both adopt Bitcoin.
Not necessarily the price of Bitcoin will rise drastically, of course it takes time.
That will only be the initial hype of Bitcoin's rise when some countries accept it.
See how El Salvador announced that it fully accepted Bitcoin, The price did rise, but after a while the price began to decline back by more than -70%.
Accepted worldwide is quite a high delusion, Bitcoin even has many enemies because of its nature that cannot be regulated by anyone or decentralized.
Governments want to regulate completely, but they will never be able to.