ROTFL ...
how many years have gone since you did your license?
A JAA PPL allows you to fly a plane registered in the country of issuance of your license everywhere in the world - in principle. If your license is expired, there is almost no way to get in the air legally without FI/FE and a skills test. Then, you can no longer revitalize your JAA, you have to go EASA Part-FCL for the renewal. Does you JAA cover CVFR as well? If not, you have to do the additional exam. If you apply for renewal, you have to present valid medical, valid language proficiency and maybe more - depending on which country your license was issued.
You may be able to fly, but you won't survive any ramp check. In the mentioned countries an expired license could be treated as terrorism, just to let you know. Also, no charter company will let you on the field without checkride and checking your papers - you don't have valid ones, you stay on the ground.
For Korea, Japan, China you need to ge acquainted with local regulations, flight restrictions (i.a. China just lowered the mandatory military clearance requirement for every flight, not to speak FPL, but you still have to be fluent in Mandarin at certain places etc etc etc).
The procedures you have to follow are quite easy - use your brain, get your license renewed with all the bells and whistles, do the respective validations for each and every country you want to fly and learn learn learn. There is no easy way for such wish.