On #formality levels in #subtitling
Languages have different ways to mark the relationship between addresser and addressee. E.g:
-built into grammar (ES, EL, DE)
-have but not use (SV).
-more than two levels (JA, KO)
https://www.encyclopedia.com/humanities/encyclopedias-almanacs-transcripts-and-maps/form-address
https://blogs.transparent.com/swedish/the-swedish-formal-you-does-it-exist/

"Come, professor" does not have to be translated literally in EL, DE, ES. We may omit "professor" as it may just be there to mark relationship (respect) rather than any other info.
E.g. "Ελάτε" or "Venga" may be enough (always depending on context of course)

In #pivotsubtitling an annotation about formality level may not cut it. The subtitler needs to discern whether it is marked (unusual in the setting, creating awkwardness) or unmarked (standard, expected formality in this situation).

Example: A high rank police official addressing a lower rank in a German show uses "Sie". In a typical situation in Greek, he would use the informal address.
How do we subtitle it? One factor maybe change of level, e.g. if they become friends and he starts using "Du".

A Swedish reporter addressing a politician in a press conference, using "du": Is this standard? Does she mean to be rude?
Usually there will be more cues to help the subtitler decide: plot, facial expressions, tone of voice.

Btw, #MT and #NMT cannot make such decisions.
As for inexperienced or untrained people, it doesn't even occur to them.