Translation:Pöllönen speaks both Danish and Norwegian.
Although the meaning is similar, it is not exactly the same. I think your sentence would be "Pöllönen osaa puhuu..." instead of "Pöllönen puhuu...". Saying "Pöllönen is able to speak" focuses on the ability, while "Pöllönen is speaking" focuses on the action.
In the contexts that this sentence would probably be used in, I think your sentence would make more sense. However, with the given Finnish sentence, "Pöllönen speaks..." is probably the most accurate translation.