Millions and millions of domestic transactions are declined simply because the chargeback risk is higher than normal.
It's not that companies don't want international customers. It's that the negative financial impact of fraud has to be heavily factored into business decisions because it's a very real and very expensive consequence.

ESO does have a number of regional and global retail partners. While this list is surely more than a little bit out of date, it's a good starting place. If you open a support ticket you can probably receive recommendations for more current retailers in your area.

https://forums.elderscrollsonline.com/en/discussion/171736/deactivation-of-fraudulently-obtained-esotu-game-keys

Malthazar wrote: »

problem is, i am brazilian but i'm currently living in paraguay, close to the border with brazil, and idk if it's possible to find anything related to ESO here. probably only the phisical copy of the disc, but nothing more.
well, i'll try contacting support and see what i find

Se você tiver alguma resposta, escreve aqui pra gente.

Thought this was going to be an 'Add more methods of payment because with these Crown Store prices, I'll have to start paying you with organs... how many kidneys for that mount?' thread

But no, I see it's serious I checked your country on a travel advice page, and they said that credit cards such as Maestro and Visa are widely accepted. That must mean that they allow for debit/credit cards. I also found this one a forum:
'[name of bank] is one of the main ones. I like their services as they basically have everything internet and phone banking, atm's, supermarket points where you can even go on Saturdays and Sundays. All banks have internet and phone banking and I think that in general banking is quite developed in Paraguay so plenty of options to shop around.' So perhaps it's just hard to find those bank branches in your specific town or something?

Then again, if they made ESO+ giftable, then this would solve the problem - you could get it with gold like other Crown Store gifts, and ZOS get their money from whoever purchased it with crowns. Anyway, hope you'll find a solution!