[litetime]

> you can use paypal [to] store EUR or USD [from yuan]

How would you do this?

If it is possible to exchange yuan to usd and keep it in paypal without a US account, I would still be very uncomfortable storing hundreds of thousands of dollars in it. It is a centralized entity that can freeze funds for any reason, be compelled to report things, make mistakes, paper trail, etc.

Being able to exchange currencies is also a step above regular banking I believe. You need access to forex markets and the associated setup and trails.