Yeah check the Appendix for some of the information gaps there. They appear to be gendered, though androgynous other than sex organs. Pregnant sranc on the fields of battle.

TUC also implies evolution for the millions of sranc that come from the coasts to overwhlem TGO near the end of TUC, which basically demands more/less traditional sexual reproduction... insofar as "IRL genetics" apply  at all in Earwaverse.

There should be plenty of sranc without actual/direct/first-person knowledge of the Inchoroi. However there does seem to be some kind of instinctual knowledge, or memetic mechanism, that at the very least elicits predictable responses... ie despite having no information about the inchoroi, they still react in ways that suggest they do whenever the wild sranc happen to run into their creators.

Interesting that you mention this considering Cursed Armada's most recent video: https://youtu.be/UGAexnagoQM

Moenghus, apparently, was captured by the Utemot, *alive*, after having spent weeks with them and had learned some rudiments of their developing "Ork" language during his captivity. Lol, kind of like Kellhus at Atrithau but Moenghus the Elder conditioned Sranc, not men. It suggests there are absolutely Sranc out there that are "native" without the No-God.

As to your question, TTT Glossary outright says there are pregnant females fighting in the First Apocalypse.

We know that there are ten times as many Sranc roaming the Ancient North today as there were during the First Apocalypse. Yet Sranc are always depicted as male, so would appear to be incapable of mating with one-another.

There is also a Sranc who says, in reference to the Old Fathers: "Father… father! We have no fathers save the earth!", which suggests the Sranc somehow gestate within the earth (like Orks!), but I seem to remember somebody mentioning a reference to female Sranc, so perhaps that is wrong.

It is possible that all Sranc spill out from Golgotterath, but if that is the case how are there wild Sranc clans who don't even know who the Inchoroi are?

But why is Sil's shield so big? Are you suggesting that the shield is a relic from the days when the Inchoroi were huge, but the Heron Spear is more recent (or was shrunk down from a previously bigger weapon)?
That still doesn't explain how Aurang was able to wrestle the Tall and win.

Into the Narrowdark by Tad Williams (8 )
The Queen of Attolia by Megan Whalen Turner (9)

Narrowdark is great, only hurt by the typical Williams style of it being essentially part one of the third book of a trilogy.  There is a lot of build up and a little bit of payoff, but plenty left hanging for the final book.  I was a bit unhappy, we get teased quite a bit about what the big bads are actually trying to do (Williams plays coy with mcguffin-like plots again), and it's clear what they are after by the end, but not why.  And the why is essentially left at "hey, I'm going to tell you, but the book is over now... next time."  It left a slightly frustrated taste.  While I'd still not call it necessary, the Brothers of the Wind ancillary book helped one of the threads to hit harder than it would have otherwise.  This series is a worthy successor to MS&T, if you liked that.  This series gets away from the basic hero's journey of MS&T and is much broader in the disparate threads he keeps going.

The Queen is likewise very good.  Sequel to the Thief, of course, and is again a shorter book that seems to be marketed as YA.  Even more so than its predecessor, this has subtlety and character work that is rarely found in other books called "YA."  Turner has a fairly unique style, which stands out more in this book.  There are big things happening, but she'll take a short paragraph to update on the status of a war or something, but the bulk of the story is her characters talking about and around the action.