You can mimic what Kentico does in portal engine sites, by detect a site visitor's culture based on the visitor's browser settings. This will provide site visitors a better experience. For example, for site visitors from Canada, French speakers will have browsers configured for French, and English speakers will have browsers configured for English. This works better for many countries. The US is another example, there are many people that prefer other languages to English, by using browser settings, you would server them better as well.
To use browser settings, you simply need to add all the cultures that you want to support to the site, and then detect the visitor’s culture by checking the “accept-language” request header. You may also want to give users a way to override the automatically detected culture, by providing a UI for them to select their preferred language. In Portal Engine sites, Kentico also checks the CMSPreferredCulture cookie, which can be different than the “accept-language” request header.
To test this, you can use the ModHeader extension in Chrome to override your "accept-language" request header.
For more information, see https://docs.kentico.com/k12/multilingual-websites/setting-up-multilingual-mvc-projects.