They already have your CV and they are calling you for a second interview, so they already think you are suitably qualified and could do the job. I'd say your goal is to connect with them and show them how well you could do it. I'd be tempted to go in without a prepared presentation, ask them what a typical work project would be, and then walk them through how you might handle it, using a whiteboard etc. if appropriate. Prompt them with questions for clarification and to keep them involved. If you can get them into a dialogue rather than reading information that they already have, I think they will be impressed.
Then again, I've never been asked to do a presentation for an interview, and this may be risky if they expect a formal presentation. And the language barrier might frustrate things. Try and get more clarification as Fintan suggests. You could play it both ways by going in with the prepared presentation but planning to go "off script" as described. Even "on-script", you could have some slides detailing how you've handled projects or situations in the past that you think are likely to form part of your work in the company.