I will update the missing translations and add any additional I receive. Thanks!
@DiapDealer. I didn't want to install QTLinguist and go through what it seemed a quite convoluted process to translate about 20-30 strings tops.
The strings are in English, if the translations folder contains a <langcode>.json file that matches Sigil's UI language it simply loads that and matches any english string to their counterpart on the file.
Pretty simple and probably not the "Qt way" but it gets the job done.
I did create a class you can find in "traductor.py" to have the ".tr" method so used in Qt and I passed the poor translator around as needed
