Multi Language support
There are two ways to
1.) Different events, categories, menu entries etc. per language.
This is the normal Joomla! way, downside is that you have separate events, with different bookings etc. But everything is nicely separated, not causing any troubles.
2.) Use Joomla language overrides for the title etc.
For example set the event title to COM_MATUKIO_MY_EVENT_TITLE and then create Joomla language override for it. See chapter Change Text (Language Overrides) for more details on language overrides.