Personally while I appreciate the updated knowledge as we learn it, and I think it would be cool to see models of such creatures in a game. I personally do not believe they belong in a JP game. It doesn't follow the JP lore at all. JP is fictional and an alternate reality to our own to put it simply and within that reality they did not have feathered variants. I mean come on, Velociraptor in the JP world is not Velociraptor in reality by any means as a good point of reference for this statement.
Due to that fact that's why it makes little sense to incorporate feathered variations. Especially when you look at it from a lore perspective. Doesn't matter what we would have 'believed' they looked like, or what fossil records were, their DNA would have held some knowledge or input to this factor. DNA isn't reliant upon the fossilized bones we found. Due to that fact feather variations realistically would have shown up in previous movies and the book itself IF that was a factor within the universe that was created. To turn around and have it suddenly transpire down the line simply because modern theories change in our reality it doesn't reflect well within the JP reality that was created. You create a plot hole of 'well why is it suddenly feathered now, when prior it wasn't?'
I suppose you could try and state the argument that better DNA extraction occurred due improved technology, filling in the gaps better for more pure DNA, However one would think that frog DNA would not have been the basis for filling in the gaps properly if utilizing this train of thought and instead it might have been instead avian DNA that would have better matched when they searched for what would fill in that gap. So again you run into plot holes within the world constructed in my opinion.
The only possible means I could see making it seem feasible and possible to happen well within the JP universe is instead of trying to state that new modern science discovered they might have had feathers. (Because again, they were dealing more in DNA then what fossils showed, and DNA would have told them much quicker if there was feathers or not) Would instead be that with experimentation in Ingen and their hybrids, they opted to try and use Avian DNA to fill in the gaps and that created feathered variations.
So more specifically within JW:E they could have avian DNA be one of the possible attributes to put in the Genetic code to cause a possible mutation that added a feathered variation within the JP world.