There is nothing in the code to prevent this, and nothing in the PayPal API specifications to pass a parameter TO PayPal telling them how to handle "this" transaction.
As you said, there appears to be no option within the PayPal profile settings to allow this.
There is a way to code for it by reading the customer's PAYERSTATUS value and if it doesn't say "Verified", act accordingly (ie: display an error alert banner and deselect the PayPal payment option even though they had already chosen it).
However, I don't see clearly "why" you would want to enforce such a restriction. A "confirmed" shipping address (Admin switch in PayPal Express Checkout module in Zen Cart) would likely give you the fraud prevention you need for peace of mind when shipping goods ... wouldn't it?
I haven't checked to see if PayPal offers "confirmed address" services to PayPal accounts outside North America. It's certainly available to more than U.S. only.
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