While major streaming platforms like Netflix or Prime Video don’t offer an official "Medieval Portuguese" setting, the community has stepped in:

Digital archives of the Cantigas de Santa Maria offer a goldmine of vocabulary for those wanting to DIY their own subtitles. Conclusion

In the Middle Ages, the language of the western Iberian Peninsula was a unified tongue. It was the language of troubadours and king-poets like Dom Dinis. When you apply this to subtitles, "você" becomes "vós," and simple modern phrases take on a melodic, archaic weight.