Anything not in English or French has to be translated. Because Skype logs are not an official document, you could probably get away with doing the translation yourself. (Some forum members have done so and gotten a visa.) Officially, CIC does not want you or a family member to be doing any of the translations.
If you have a lot of other evidence your relationship is genuine, you could submit less of your Skype log. Just send in a sampling, stating you have more if the visa officer wants to see it (they don't usually ask for more). Then you won't have as much to translate. If you really need this evidence because you don't have much else, get the translation done by someone who is not a family member, and send in more of it.
You say the language is Creole. What kind? Could you write a sentence or two as a sample? If it is close enough to English or French, I would say it would not need to be translated at all.