Best place to find legendary annointed shields?

Does anyone have any good farms? I’ve tried SS on M4 many times, I might come away with one after about 20 rounds.
I’ve been running Freddy the Traitor like crazy yesterday and today but every single shield that drops is unannointed. I’m beginning think only weapons he drops can come annointed.
I would really prefer to not farm their dedicated enemies as it is beyond tedious at this point with such a big world drop rate.
Has anyone noticed shields dropping more in Slaughterstar or Cistern of Slaughter?
Thanx and Happy Holidays