International patent in Asia: where does it really serve and which model?

I’m planning Thailand, Japan and Indonesia over a year and would like to rent cars or scooters only in some areas. Online I find contradictory indications between Geneva 1949, Vienna 1968 and simple Italian license. I do not want to find out at the counter that the document is not accepted or, worse, have problems with insurance after an accident. I look for recent experiences and official sources to check before departure. I am interested in a comparison based on recent experiences: indicated travel period, what…