I've two store website with a single inventory with different currencies. It doesn't want any currency conversion as I want to have a defined price for each website. I changed the scope of price to Website and updated different prices to my products. When clicked on a category in a storefront, I got the price as a base and when clicking on the product, the product page showed the right currency. For example, assume my base currency is INR, have another store with USD. In USD website, when I click in a category, the catalog list page showing the price INR and when click a specific product, the price displayed in USD.
For multicurrency you have to set multiple websites not stores because in scope of store price will be always converted with regards to current conversion rates. It is because a website can have only one base currency and all other currencies are always calculated as a result of conversion.