UK, Australia, New Zealand, Japan and South Africa as main ones I think. Along with numerous Caribbean islands and various ex british colonies. A few other African nations too. Might be nice just to get a few classic british sports cars and maybe one or 2 JDM exclusive cars. I mean the R32/33/34 get suggested loads, I am not saying we need one of those exact cars, but something similar that lore wise was only offered in japan. Or, people have been asking for japanese trucks, old datsun pickup in RHD (though these were offered LHD).
This is something I've been thinking about too, although not so much as totally new vehicles, but variations of vehicles we already have. The ETK 800 series for example is LHD, but all of the big German cars are sold globally and are particularly popular in places like the UK, which uses RHD cars. Is there any chance we could see both options on globalised vehicles like the ETK and Pessima? On a slightly different note, some cars could do with an option for the longer European-style license plates. Yet again the ETK is a perfect candidate (particularly the Polizei version which looks odd with a US-style plate on it), but many others already have space for larger plates on the bumpers (Bollide, Pessimas, SBR4, Sunburst, Pigeon).