Having been living and traveling in some interesting places, you can do it in modern EU spec vehical, but check with VW as to what support is available in counties you are going to.
Usually if it’s not so well developed they are unlikely to have anything more than Euro3 spec and fuel to match, and apart from components failing it’s the high sulphur diesel that will block the partical filter and kill the cat and the lack of Adblue.
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It’s not all doom & gloom Turkey has Euro5&6 and 50 ppm diesel but they don’t mention if it’s to EN590, they also have 1,000 ppm for agri and it’s easy to get ripped off, VW has the transporter there with Euro6 up to 150 ps, so should be no issue.
Any further east I would advise not taking anything modern, there’s a big dark gap between Iran and East Asian seaboard anything more than Euro2 forget it.
But as many know Murphy is always around somewhere.