its very hard to say what it is. common stuff includes plugs, leads, coils, 02 sensor, but it could even be something more mechanical like a sticking valve. the last clio sport i did with a misfire, was just lack of fuel, lol.
Good new is if you eml has been on, it should have stored the fault. get it read, before you start replacing stuff. if you just get a quick clip test at renault it shouldn't be that dear. I/ other members can help translate the fault codes for you, with the help of dialogis and actis(renault.net).