With "direct to you," you are responsible for settling the VAT on the sale.
With "collect by Itch," the store is Itch, not you, and therefore you are not responsible for paying VAT.
In practice, it's impossible for a store to have agreements with all countries, and they typically operate based on international transactions. That is, a person who buys from Mexico, for example, makes an international purchase to the US, and in that case, it will depend on the legislation of each country.
What I've seen is that in some countries, it's the bank that, when it detects that it's an international purchase, applies the VAT as a commission. But this depends on the laws of each country, and in many, it simply remains a gray area, and they don't actually charge you any VAT.
Normally, this isn't a problem because you're not the store and therefore you're not selling. What is certain is that when you receive the Itch payment, you may be required to report that money to your country's tax authorities, but it's best to consult with a lawyer in your country of residence.