Can I convert prices on my Buy Button?
The Shopify Buy Button is a way of selling your products in any web site outside Shopify.
Unfortunately, Shopify does not provide a system for the apps to run on the 'Buy Button' sales channel. Shopify apps are only available on the 'Online Store' sales channel.
For that reason, prices cannot be converted on any place outside your Shopify store, including the 'Buy Button'.