I think he was referring to her division at the CIA, since that's what agency she was with in Civil War.

To be fair it could be either the CIA or S.H.I.E.L.D. Both fit the brief. Probably gonna have to wait till Armor Wars, unless Sharon is gonna pop up in a few along the way to build up the mystery of what she's doing.

She will probably appear in Captain America 4 when that happens

Probably yes, Armor wars seems more likely to turn up first. Then again maybe I'm wrong and she won't appear in that, it just feels like that's an obvious fit.

Yeah it could be either CIA or SHIELD. But Sharon is the Power Broker, and she obviously has something evil planned.

Uh. If she is working for S.H.I.E.L.D, I don't think she's working for Mack. Because Marvel seems to ignore the tv shows other than Disney+.

Well she is no longer SHIELD. It appears she is working for someone else but don’t know who it is. If she wasn’t the Power Broker then I would say yes

I may not know this, as I am quite new to fandom. Why does it say "edited by the administrators" under my post? As far as I can recall i didn't post anything offensive or inappropriate.

It would have been nice to be an allusion to S.H.I.E.L.D. but more likely her most recent position with the C.I.A. -- given she was stationed at the Joint Counter Terrorist Centre in Berlin, I suppose she was part of the C.I.A.'s National Clandestine Service in Counterterrorism. Or if not the NCS, then the intelligence division aka the Directorate of Analysis's Terrorism Analysis or Russian and European Analysis.