Banner slider is a premium real estate of any website. That is the first thing that users sees and search engine crawls. We implement and recommend a good banner slider like Revolution slider. This allows you to have text overlays and embed call to actions. Both are very important as text can be crawled by search engine and with right call to action you take the user directly to part of the funner and enable goal conversions.
There are varying degrees to which you can enable/implement localization/internationalization. In simplest form, you can use google translate to translate page in multiple languages. This is far from perfect approach. Alternately, a multi-language enabled website will allow you to enter translations. There is more to it than that. What about text in graphics/images? Same thing applies to currency. In simplest form one can convert currency from USD to local current using a conversion rate. But for a global company, the price at which you may want to sell in US market vs Europe may be different. The taxes/VAT may be different. UK/Europe stores display prices including VAT. To summarize, for a good implementation, consult a localization and internationalization expert.