On how you display your prices:
In the EU you're not allowed to advertise a price without all taxes. This means that per country you need to know the VAT % and adjust the price accordingly. You cannot change the price per EU country. You set a base price for the EU and add VAT. Since VAT differs per country this will cause non-round numbers. But this is expected.
Looks like the EU finds pricing a non-physical product on a country-by-country basis to be price discrimination against EU nationals:
"When you buy goods online in the EU, prices may vary from country to country or across different versions of the same website, for example due to differences in delivery costs. However, if you buy goods online without cross-border delivery – such as when you buy something online which you intend to collect from a trader or shop yourself – you should have access to the same prices and special offers as buyers living in that EU country." [1]
[1] https://europa.eu/youreurope/citizens/consumers/shopping/pri...
What I understand from there is that you cannot have prices different for people in a country, and for those who buy from another country.
I am French. I could buy something for X€ in Germany, and someone in Germany would have the same price. But I can buy this for Y€ in France and Z€ in spain.
This is a common thing to do with, say, Amazon where I can buy something in Germany because the price is better and have it delivered from France to France (the delivery can also be cross-border, it depends)
Why couldn't that have different prices per country?