Playing on PC, in Operations mode, on any map. Bug is 100% repeatable. Skill tiers II and III of Chain Hit, among other things, is bugged for Orlock Brawlers. The system shows targets for Chain Hit as out of range, even while other melee skills are usable.
EDIT: All image uploaded to imgur, as the other site was behaving oddly: https://imgur.com/a/oWlPdsi
PHOTO 1: As you can see in Photo 1; the game has just started and my Brawler is approaching an Escher fighter who has strayed too close. Chain Hit is not even an option as an Offensive Action because I am out of melee range, but I have made it appear by showing unavailable actions to make sure it was still there.
PHOTO 2: In Photo 2, I have closed to melee range and Chain Hit is again not an option, though I have made it appear by showing unavailable actions. As you can see, the system says that the Escher fighter is out of range for Chain Hit, despite Heroic Onslaught being a viable option (you can tell this because it is not dimmed). Note that the Fighter Info shows that I have Fury, Momentum, and Chain Hit buffs active, even though I have taken no actions, have had no previous turns, and clearly could not Chain Hit even if I wanted to. My AP and MP are both still full (50 of 50) as I have not committed to the attack.
PHOTO 3: In Photo 3 can clearly see that Heroic Onslaught is viable, even though Chain Hit is still not available.
TLDR: Chain Hit (at least tiers II and III) do not work for Orlock Brawlers. It is NOT an AP, buff or debuff issue. The system thinks Orlock fighters are out of range for some reason, despite other melee skills being available. Also important to note that this is not the case for Escher or Goliath Brawlers. Both my Escher and Goliath Brawlers can use all tiers of Chain Hit without problems.
POST PATCH UPDATE: Patch did not correct the issue, despite what the patch notes say. Like Weapons Cleaning Kits and Cellular Reconstruction Serum, nothing has changed - it's literally exactly the same.
POST PATCH SCREEN SHOTS: https://imgur.com/a/I7JfODO