Similarly to your commenters I have a feeling that you may be looking at it in a way that will take much more of your time than perhaps it's required. :-)
Nevertheless:
- I know not of such a tool or pre-gen already existing that meet your criteria (but see update below thanks to @Ahriman)
- Have you tried the forums? If anyone made something like it, most likely place for it to be published is here: http://privateerpressforums.com/forum.php
- My proposals below.
Why I think you may not need it
As a result I find myself in need of a wide variety of NPCs for
encounters in Cygnar. Encounters in this area would be mostly people
instead of creatures, especially inside the city. It would take me a
lot of time to generate the large number of the various NPCs that I
think would be required (pirates, smugglers, military, highwaymen,
merchants, Cyriss cultists, etc.).
Even the encounter sheet proposed by publisher rather focuses on conflict situations. The sheet: http://files.privateerpress.com/ironkingdoms/documents/Game_Master_Encounter_Sheet.pdf
That is because it's very demanding to create scores of characters that are enough to fill an entire city.
Most of the work going in it is unneeded. Mostly your players will just "observe" the NPC (fisherman fishes, shopkeeper haggles, beggar asks for money, etc.). Generating names, archetypes, stats, weapons for all those? Lots of work. It's much better spent thinking about crucial moments (how will they all react when player A pulls out his incredibly-well crafted steam pistol he spent hour drawing?).
Usually one either simplifies character generation (crazy prepares) or thinks fast or encourages player choices (sign "the adventure this way") and prepares along these lines.
Write your own table / chargen
Will suit you the best, will be tailored for you. My Cygnar is different than yours. Heck, my Highgate is different than yours. Thus, my table assumes there are many gunmages in Cygnar, while your campaign may want none (because recent laws blah blah blah).
Yes, it is hard work, but it may pay off. My friend does it often, just not to be burdened with having to think of yet another unimportant NPC.
Decide on factors and probability, write it down, then just roll.
Tweak the process till you have minimum rolls with good enough results (all the stats and info you need. For race, 1 in 10 people will be an elf, 1 in 10 a dwarf, rest are humans. Factors are human, elf, dwarf, probabilities: 1/10, 1/10, 8/10.
Simplify it
- Random (but good enough) names table that gives you 100 names and surnames.
- Short (1 sentence) description: adjective mood profession (that gets randomized). "Honest irate pirate", "large angry soldier" or "deceitful happy shopkeeper".
Two rolls will now bring to live "Harrison Ford, crafty amused carpenter" or "Morton Rourke, competent middle-aged lieutenant" or...
Simplify stats
Choose what is average. Is average strength in your Highgate 3 or 5? Now, just assume most NPCs have average stats, but modify "on-the-fly" (only when needed). competent soldier means +2, drunk soldier is +1 str but -1 agi etc.
Shift it to players
Have players create (each) three characters that they have some positive relations with and one (each) character they know, but who doesn't like them (or who they cannot trust or plain dislike). They'll use those characters for most interactions and they'll flesh them out for you. Now, you only need to include them in campaign.
A missive arrived from your cousin who works as city watchman, stating
only few words "When you read it, I may well be in the hands of those
damn cultists, protect my wife my friend".
Or less drastic and not taking a character away
"lately bad rumours are circulating about you my cousin among my
fellow watchmen. Care dining with me tonight, so we may unroot the
cause?"
Think fast aka improvise
Spend some times thinking about where your players will be. What they'll be doing. When preparing to session, sketch some crucial areas and think who works there, lives there, etc. Now, when time comes and a player tells you something unexpected (like, I'm barging into that OTHER room) you will find yourself knowing who just might be inside and how will they react.
The tool
Thanks to @Ahriman's comment, there's a tool that while not exactly what you asked for, may somewhat help still:
Quick, simple character descriptions, generic or for specific
settings.
http://www.seventhsanctum.com/generate.php?Genname=quickchar
Some examples:
The dexterous noble.
The joyful, hateful healer.
The unhealthy, social coachman who lives under a curse.
The athletic, spendthrift seer.
The young, combative demonologist.
The indecisive, patriotic druid.
The snide, tactless fisherman.
The blacksmith who has a divine connection.
Tool is known as the Quick Character Generator of Seventh Sanctum.