I don't know if Windlass Steelcrafts of India is still making reproductions of WW1 Trench knives, but I know they used to offer such items a while back.
While their reproductions may not be of the high end category, they tend to be decent and have hand forged blades made of carbon steel.
The following knife was one of such offerings by Windlass Steelcrafts. It's their rendition/repro of a WW1 English punch/push dagger that was a fairly popular private purchase by soldiers heading to the WW1 Trenches.
While not exact or perfectly made copies, by adding in a wee bit of judicious hand done refining, they can be pretty good representations of the originals.
On mine shown here, I cleaned up some of the rougher areas of it's aluminum handle casting and smoothed out the overall handle's surface. It would need a sharpening of the blade for it to be sharp, (since it came with a dull/flat edge), but for my personal shadow box use, it didn't receive that extra effort.
It's definitely a hand crafted item that has a solid feel to it's build.
It's probably about as solid as the originals likely were, if not more so.
Actually, although these are not refined reproductions, that judicious work I mentioned doing above, is all that it takes to get them to the refinement of the originals, since they themselves were not exactly of a high refinement either

Cost wound up being just slightly less than what a basic modern KaBar can be had for, which isn't dirt cheap, but acceptable, especially when one considers that they are hand crafted, (although a wee bit crude to go with it). Their hand made nature probably compares to how the originals were made. In that sense, I think that's a pro, not a con, since it adds a little pinch of authenticity to them over what modern high tech machinery would churn out.