Regarding parallel corpora, the bible is a common source that contains translations to many of these languages, although it is not always straightforward to extract the content in a digital format.
there are some projects that offer parallel content through a web search interface, e.g., Axolotl (Spanish-Nahuatl parallel corpus) that was mainly gathered from non-digital sources (books from several domains), the documents have dialectal, diachronic and orthographic variation (Gutierrez-Vasques et al., 2016).