No, it doesn’t work.
Have a look at this topic for a few ideas: How to structure a multilingual community.
For the case of a forum where users are unlikely to be able to understand the site’s default locale, probably the most important thing is to make sure the user’s locale set correctly when they create their account. That way they will be able to navigate the forum, even if they can’t read some of the content. To do this, first make sure that the allow user locale Site Setting is enabled. When enabled, users will be able to set their locale on their preferences page.
Having to set the locale preferences on a site where users can’t understand the default locale could be difficult. There are two options I know of to get around this. You can either use SSO and set the locale with an SSO parameter, or enable the set locale from accept language header Site Setting.
Note: There is an issue with setting the locale for anonymous users for on sites that are using a CDN. It can cause the wrong locale files to be served to anonymous users. See: Swedish? meta just showed me the UI in Swedish .