They help you get your company set up (with e-residence) and then hook into either Transferwise or LHV for banking (and stripe, etc flows into that).
Very friendly as well, I'm in Estonia currently and I dropped into their office yesterday to say hi.
For now I'm just using resellers like Copecart/Digistore24/Paddle/FastSpring to handle all the global B2C VAT stuff for me.
This is the best summary I found of the situation so far: https://quaderno.io/resources/eu-vat-guide/
Basically I arrived at the conclusion that it's impossible for me as a small business to do global B2C VAT (not just calculation, but also actual remittance) myself, and thus am using resellers (Copecart, Digistore24, Paddle, FastSpring) that do all this for you by being a complete middleman in the transaction. Of course they then also take a larger cut than something more light-weight like Stripe. I wish Stripe also supported global VAT / sales tax remittance.
EDIT: See also https://www.youtube.com/watch?v=MowACIitd1s and https://www.youtube.com/watch?v=sO4nzWWMAvg