I mean, you argued against yourself by using robots as a non-alien example and then admitted they’re not a species either…
How about ‘race’? That’s not a politically-charged term at all.
I’ll explain my thinking about alien though (even though I know I’m on the losing side) - ‘species’ feels too scientific for a website which is essentially about stories. Words like ‘location’, ‘character’ (and the ‘not being used’ terms like villain, companion etc) fit with a story aesthetic. I think ‘alien’ fits better with that aesthetic than ‘species’.
There’s also the term “beings”, which might be a bit too out there, but we could all argue that robots are beings, even if they aren’t aliens or species
I used “Historical Characters” to mean people like Da Vinci or Churchill, then found they used Davina McCall in an episode and she’s not a fictional character but wouldn’t call her Historical either (sorry Davina).
I think the problem is where you draw the line on ‘Historical’ character - take the Beatles for example who feature in The Devil’s Chord. Are Lennon and Harrison ‘historical’ but McCartney and Starr not because they are alive? What about Cilla? Is WW2 the cut off.
Call the Midwife could be considered a historical show but is set at a time my parents lived through (and rapidly approaching when my generation were born).
So I think what I’m saying is ‘real life’ but maybe ‘real life figure’ rather than ‘character’ (as you also run into the issue of how fictionalised the ‘real life figure is’ such as Churchill or Lennon (who most Beatles fans were up in arms over because he was wearing those glasses at the wrong time in his life…)