Apparently it's either not a requirement or not so strongly enforced in the US and EU as it is in Japan, or that was my understanding from the conversation.

Update: searching a bit and reading about the EU sales taxes, there are few rules but overall it's pretty clear you either don't pay or pay local sales taxes even for international sales for low-volume B2C sales (sorry it's Spanish): https://www.carrilloasesores.com/post/iva-de-ventas-por-inte...