There is not an uniform policy about it and each country has their own rules and demands but normally they accept the ones from the banner of the boat, providing they have on that country a sensible regulation on safety equipment
(on the ones that have regulation the demands are not so different).
If you have several types of flares (several of each type)with a valid date you should be alright. If you have flares out of date dispose them. That can have a contraproducente effect on the police.
Need also a liferaft
, fire extinguishers (valid), life jackets, a medical
box and in some cases an Epirb
, but probably you have all that.