Thats part of mmod not project hl2, project hl2 can change that but it only happens if you have mmod, which isn't available through workshop port right now (to my knowledge), only weapons, animations, and sounds.

You can always get the pre-Anniversary version through the betas menu to get the MMOD running and get that if you want :)
iirc, the creator of MMOD is busy right now updating the original MMOD for Half Life 1