I think the promo Triss -- you're right, she does look off, her nose is definitely too small and seems to be too low on her face and generally her face is quite different from tw2 Triss. But between the two differing models we see in the cosplay guide -- as you call them render Triss and gameplay Triss -- I actually think they are both more or less representations of the same person -- more than the promo shot. How to describe it? If render Triss was a real person, then gameplay Triss is someone's interpretation, if that makes sense. I see what you mean about the differences you mention, but I think they are more like 'softer' rather than smaller, and they're sculpted in such a way that is more realistic than the gameplay version.
See, I'm uncertain about those two models -- what we call gameplay and render -- because they could actually both be gameplay. I think it's very possible what we call render Triss is actually a newer version that we just haven't seen in any footage yet. I think render Triss is fine -- she seems more unique facially in comparison to Ciri, but still draws some recognisability from tw2 Triss even thought she's quite different. I'm pretty easy to please tbh, though.
Yeah, the two cosplay guide models are still similar enough, just the "render" Triss has sharper features, although I do prefer the "gameplay" version. Just personal preference and its similarity to Witcher 2's Triss. I'm pretty sure the "render" model isn't in-game, though. The quality of the model and lighting seems inconsistent with the other cosplay guide models to me, while the hidden picture looks like the others. The steelbook artwork, which has Yennefer looking like the Elder Blood trailer, seems to show Triss looking much the same as in the Sword of Destiny trailer.