Before posting the question above, I had searched for similar questions, but found nothing. Since my post a previous question popped up from February 2021 asking similar question. I therefore presume Mozilla are still working on multi-currency payments on their website.

Hello!

The subscription charge amount for the Mozilla VPN is 4.99$ a month. Unfortunately, we aren't offering subscription plans in any currency except US dollar at the moment, conversion charges may apply. Our development team is still working on adding multi-currency support in a future release.

I hope you find this helpful,