Hi Gaurav,
The biggest hurdle is not generating the feed, but ensuring your site adheres to Google's region-specific policies on each product page. For example, although your shop allows approximation of different currencies by manually selecting the currency from a drop-down, it would still be suspended immediately once Google runs their automated/manual checks on your product pages as they would not show (by default) VAT-inclusive pricing in GPB.
We're working hard on enabling/facilitating this use case, but for the moment you could only really do this using two region-specific shopify stores.
Regards,
Shawn