Frankly the 41mm forks probably have enough torsional rigidity that a brace isn’t necessary. I rode my Bobber Black (43mm forks) without front fender for a week and didn’t notice any vagueness/wobble in the twisties. I reinstalled them due to splatter. Furthermore Triumph didn’t seem to think it necessary (or that the fender provided sufficient stability). Probably doesn’t hurt to install it but likely unnecessary given the Bobber’s intended use.
I have seen a few pics of this bike without a fork brace but thats just a posing pic of course, looked for fork braces for this bike on inter web and none seem to exist....I think Roland Sands needs to jump on this bike and make a few parts....thx anyway