Subtitles do not change watch progress
Watching with subs is still watching. A tracker that treats dubbed versus subbed as two shows will split your count and your household peace.
One show, one progress bar. Language is a playback setting. nextepisode should not fork a season because you switched to the original audio.
Household disagreement
If one of you needs subs and the other wants dub, that is a TV setting. It is not two rows in the tracker unless you truly rewatch.
Fansub episode numbers
Unofficial numbers still have to map to the database episode. Progress on a fansub label that is N+1 is how you skip a week.
Frequently asked questions
What if the dub cuts an episode?
Track the canonical list. Note the cut. Do not delete the row.
Can I track a language rewatch?
As a rewatch, yes. As a second show, no.