Same here. In vanilla, the HK-50 units can't fire at any of the party. They just stand there and can't attack, while HK-47 is removed from the party but just stands there.
In TSLRCM, I've noticed the vanilla HK-47 spawns still function this way (i.e. the squad located outside the Enclave on Dantooine and a couple others), but the additional HK-50 spawns (such as the squads of them that show up after blowing up GO-TO's Yacht) don't. In the additional spawns added by TSLRCM, HK-47 is removed from party as normal, and the HK-50s give their embarrassed speech about how they can't fire, but then they proceed to fire at everyone in the party except HK-47.
Other times having HK-47 in the party on Nar Shadaa causes TSLRCM added HK-50 squads to not spawn at all (e.g. when you have to play as Bao-Dur, Atton, and one additional party member and try to rescue the Exile. No HK-47, I run into a few squads of HK-50s in addition to the Gand and Zhugs. Reloaded and selected HK-47, and no HK-50s in sight. I'm presuming this was intentional though?).
No mods installed except TSL 1.8.5.