Hi Andreas,
It looks like you are using WPML and I’m sorry to say we don’t yet support this for Filter Bar:
theeventscalendar.com/knowledgebase/wpml-support
Behind the scenes, WPML creates different posts for different languages and in a scenario like this where posts of one type (such as events) are linked to posts of various other types (such as venues and organizers) there’s a chance that those relationships may have broken down.
Are the venues for those events also translated into Swedish and German – and are the Swedish and German versions of the events linked to those same translated venues?